Actual source code: openglops.c
petsc-3.7.1 2016-05-15
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      2: /*
      3:     Defines the operations for the OpenGL PetscDraw implementation.

      5:     The eventual plan is to have a window system independent portion (that only uses gl...() routines) plus
      6:       several implementations for different Window interfaces:
      7:        --  glut (implmented)
      8:        --  Apple IOS  EAGLContext  https://developer.apple.com/library/ios/#documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/WorkingwithOpenGLESContexts/WorkingwithOpenGLESContexts.html#//apple_ref/doc/uid/TP40008793-CH2-SW1
      9:        --  Apple  NSOpenGLView  http://developer.apple.com/library/mac/#documentation/graphicsimaging/conceptual/OpenGL-MacProgGuide/opengl_pg_concepts/opengl_pg_concepts.html#//apple_ref/doc/uid/TP40001987-CH208-SW1
     10:        --  Apple  CGLContextObj http://developer.apple.com/library/mac/#documentation/graphicsimaging/Reference/CGL_OpenGL/Reference/reference.html#//apple_ref/doc/uid/TP40001186
     11: */

     13: #include <petsc/private/drawimpl.h>  /*I  "petscsys.h" I*/
     14: #if defined(PETSC_HAVE_OPENGLES)
     15: #import <UIKit/UIKit.h>
     16: #import <GLKit/GLKit.h>
     17: #import <OpenGLES/EAGLDrawable.h>
     18: #import <OpenGLES/ES2/gl.h>
     19: #elif defined(PETSC_HAVE_GLUT)
     20: #if defined(__APPLE__) || defined(MACOSX)
     21: #include <AvailabilityMacros.h>
     22: #include <OpenGL/gl.h>
     23: #include <OpenGL/glu.h>
     24: #else
     25: #include <GL/gl.h>
     26: #include <GL/glu.h>
     27: #endif
     28: #endif

     31: /*
     32:      These macros transform from the users coordinates to the OpenGL coordinates of -1,-1 to 1,1.
     33: */
     34: #define XTRANS(draw,x)  (-1.0 + 2.0*((draw)->port_xl + (((x - (draw)->coor_xl)*((draw)->port_xr - (draw)->port_xl))/((draw)->coor_xr - (draw)->coor_xl))))
     35: #define YTRANS(draw,y)  (-1.0 + 2.0*((draw)->port_yl + (((y - (draw)->coor_yl)*((draw)->port_yr - (draw)->port_yl))/((draw)->coor_yr - (draw)->coor_yl))))

     37: /*
     38:      These macros transform from the users coordinates to pixel coordinates.
     39: */
     40: #define XPTRANS(draw,win,x) (int)(((win)->w)*((draw)->port_xl + (((x - (draw)->coor_xl)*((draw)->port_xr - (draw)->port_xl))/((draw)->coor_xr - (draw)->coor_xl))))
     41: #define YPTRANS(draw,win,y) (int)(((win)->h)*(1.0-(draw)->port_yl - (((y - (draw)->coor_yl)*((draw)->port_yr - (draw)->port_yl))/((draw)->coor_yr - (draw)->coor_yl))))

     43: static unsigned char rcolor[256],gcolor[256],bcolor[256];
     46: static PetscErrorCode InitializeColors(void)
     47: {

     51:   rcolor[PETSC_DRAW_WHITE]           = 255;
     52:   gcolor[PETSC_DRAW_WHITE]           = 255;
     53:   bcolor[PETSC_DRAW_WHITE]           = 255;
     54:   rcolor[PETSC_DRAW_BLACK]           =   0;
     55:   gcolor[PETSC_DRAW_BLACK]           =   0;
     56:   bcolor[PETSC_DRAW_BLACK]           =   0;
     57:   rcolor[PETSC_DRAW_RED]             = 255;
     58:   gcolor[PETSC_DRAW_RED]             =   0;
     59:   bcolor[PETSC_DRAW_RED]             =   0;
     60:   rcolor[PETSC_DRAW_GREEN]           =   0;
     61:   gcolor[PETSC_DRAW_GREEN]           = 128;
     62:   bcolor[PETSC_DRAW_GREEN]           =   0;
     63:   rcolor[PETSC_DRAW_CYAN]            =   0;
     64:   gcolor[PETSC_DRAW_CYAN]            = 139;
     65:   bcolor[PETSC_DRAW_CYAN]            = 139;
     66:   rcolor[PETSC_DRAW_BLUE]            =   0;
     67:   gcolor[PETSC_DRAW_BLUE]            =   0;
     68:   bcolor[PETSC_DRAW_BLUE]            = 255;
     69:   rcolor[PETSC_DRAW_MAGENTA]         = 255;
     70:   gcolor[PETSC_DRAW_MAGENTA]         =   0;
     71:   bcolor[PETSC_DRAW_MAGENTA]         = 255;
     72:   rcolor[PETSC_DRAW_AQUAMARINE]      = 127;
     73:   gcolor[PETSC_DRAW_AQUAMARINE]      = 255;
     74:   bcolor[PETSC_DRAW_AQUAMARINE]      = 212;
     75:   rcolor[PETSC_DRAW_FORESTGREEN]     =  34;
     76:   gcolor[PETSC_DRAW_FORESTGREEN]     = 139;
     77:   bcolor[PETSC_DRAW_FORESTGREEN]     =  34;
     78:   rcolor[PETSC_DRAW_ORANGE]          = 255;
     79:   gcolor[PETSC_DRAW_ORANGE]          = 165;
     80:   bcolor[PETSC_DRAW_ORANGE]          =   0;
     81:   rcolor[PETSC_DRAW_VIOLET]          = 238;
     82:   gcolor[PETSC_DRAW_VIOLET]          = 130;
     83:   bcolor[PETSC_DRAW_VIOLET]          = 238;
     84:   rcolor[PETSC_DRAW_BROWN]           = 165;
     85:   gcolor[PETSC_DRAW_BROWN]           =  42;
     86:   bcolor[PETSC_DRAW_BROWN]           =  42;
     87:   rcolor[PETSC_DRAW_PINK]            = 255;
     88:   gcolor[PETSC_DRAW_PINK]            = 192;
     89:   bcolor[PETSC_DRAW_PINK]            = 203;
     90:   rcolor[PETSC_DRAW_CORAL]           = 255;
     91:   gcolor[PETSC_DRAW_CORAL]           = 127;
     92:   bcolor[PETSC_DRAW_CORAL]           =  80;
     93:   rcolor[PETSC_DRAW_GRAY]            = 128;
     94:   gcolor[PETSC_DRAW_GRAY]            = 128;
     95:   bcolor[PETSC_DRAW_GRAY]            = 128;
     96:   rcolor[PETSC_DRAW_YELLOW]          = 255;
     97:   gcolor[PETSC_DRAW_YELLOW]          = 255;
     98:   bcolor[PETSC_DRAW_YELLOW]          =   0;
     99:   rcolor[PETSC_DRAW_GOLD]            = 255;
    100:   gcolor[PETSC_DRAW_GOLD]            = 215;
    101:   bcolor[PETSC_DRAW_GOLD]            =   0;
    102:   rcolor[PETSC_DRAW_LIGHTPINK]       = 255;
    103:   gcolor[PETSC_DRAW_LIGHTPINK]       = 182;
    104:   bcolor[PETSC_DRAW_LIGHTPINK]       = 193;
    105:   rcolor[PETSC_DRAW_MEDIUMTURQUOISE] =  72;
    106:   gcolor[PETSC_DRAW_MEDIUMTURQUOISE] = 209;
    107:   bcolor[PETSC_DRAW_MEDIUMTURQUOISE] = 204;
    108:   rcolor[PETSC_DRAW_KHAKI]           = 240;
    109:   gcolor[PETSC_DRAW_KHAKI]           = 230;
    110:   bcolor[PETSC_DRAW_KHAKI]           = 140;
    111:   rcolor[PETSC_DRAW_DIMGRAY]         = 105;
    112:   gcolor[PETSC_DRAW_DIMGRAY]         = 105;
    113:   bcolor[PETSC_DRAW_DIMGRAY]         = 105;
    114:   rcolor[PETSC_DRAW_YELLOWGREEN]     =  54;
    115:   gcolor[PETSC_DRAW_YELLOWGREEN]     = 205;
    116:   bcolor[PETSC_DRAW_YELLOWGREEN]     =  50;
    117:   rcolor[PETSC_DRAW_SKYBLUE]         = 135;
    118:   gcolor[PETSC_DRAW_SKYBLUE]         = 206;
    119:   bcolor[PETSC_DRAW_SKYBLUE]         = 235;
    120:   rcolor[PETSC_DRAW_DARKGREEN]       =   0;
    121:   gcolor[PETSC_DRAW_DARKGREEN]       = 100;
    122:   bcolor[PETSC_DRAW_DARKGREEN]       =   0;
    123:   rcolor[PETSC_DRAW_NAVYBLUE]        =   0;
    124:   gcolor[PETSC_DRAW_NAVYBLUE]        =   0;
    125:   bcolor[PETSC_DRAW_NAVYBLUE]        = 128;
    126:   rcolor[PETSC_DRAW_SANDYBROWN]      = 244;
    127:   gcolor[PETSC_DRAW_SANDYBROWN]      = 164;
    128:   bcolor[PETSC_DRAW_SANDYBROWN]      =  96;
    129:   rcolor[PETSC_DRAW_CADETBLUE]       =  95;
    130:   gcolor[PETSC_DRAW_CADETBLUE]       = 158;
    131:   bcolor[PETSC_DRAW_CADETBLUE]       = 160;
    132:   rcolor[PETSC_DRAW_POWDERBLUE]      = 176;
    133:   gcolor[PETSC_DRAW_POWDERBLUE]      = 224;
    134:   bcolor[PETSC_DRAW_POWDERBLUE]      = 230;
    135:   rcolor[PETSC_DRAW_DEEPPINK]        = 255;
    136:   gcolor[PETSC_DRAW_DEEPPINK]        =  20;
    137:   bcolor[PETSC_DRAW_DEEPPINK]        = 147;
    138:   rcolor[PETSC_DRAW_THISTLE]         = 216;
    139:   gcolor[PETSC_DRAW_THISTLE]         = 191;
    140:   bcolor[PETSC_DRAW_THISTLE]         = 216;
    141:   rcolor[PETSC_DRAW_LIMEGREEN]       =  50;
    142:   gcolor[PETSC_DRAW_LIMEGREEN]       = 205;
    143:   bcolor[PETSC_DRAW_LIMEGREEN]       =  50;
    144:   rcolor[PETSC_DRAW_LAVENDERBLUSH]   = 255;
    145:   gcolor[PETSC_DRAW_LAVENDERBLUSH]   = 240;
    146:   bcolor[PETSC_DRAW_LAVENDERBLUSH]   = 245;
    147:   rcolor[PETSC_DRAW_PLUM]            = 221;
    148:   gcolor[PETSC_DRAW_PLUM]            = 160;
    149:   bcolor[PETSC_DRAW_PLUM]            = 221;

    151:   PetscDrawUtilitySetCmap(NULL,256-PETSC_DRAW_BASIC_COLORS,rcolor+PETSC_DRAW_BASIC_COLORS,gcolor+PETSC_DRAW_BASIC_COLORS,bcolor+PETSC_DRAW_BASIC_COLORS);
    152:   return(0);
    153: }

    155: static GLuint vertexshader,fragmentshader,shaderprogram;
    158: static PetscErrorCode InitializeShader(void)
    159: {
    160:   const char *vertexsource = "attribute vec2 position;\
    161:                               attribute vec3 color; \
    162:                               varying vec4 vColor;\
    163:                               void main(void)\
    164:                               {\
    165:                                 vColor = vec4(color,0.50);\
    166:                                 gl_Position = vec4(position,0.0,1.0);\
    167:                               }\n";
    168: #if defined(PETSC_HAVE_GLUT)
    169:   const char *fragmentsource = "varying vec4 vColor;\
    170:                                 void main (void)\
    171:                                 {\
    172:                                   gl_FragColor = vColor; \
    173:                                 }\n";
    174: #else
    175:   const char *fragmentsource = "precision mediump float;\
    176:                                 varying vec4 vColor;\
    177:                                 void main (void)\
    178:                                 {\
    179:                                   gl_FragColor = vColor; \
    180:                                 }\n";
    181: #endif
    182:   int    isCompiled_VS, isCompiled_FS;
    183:   int    isLinked;
    184:   GLenum err;

    187:   /*  http://www.opengl.org/wiki/OpenGL_Shading_Language */
    188:   /* Create an empty vertex shader handle */
    189:   vertexshader = glCreateShader(GL_VERTEX_SHADER);

    191:   /* Send the vertex shader source code to GL */
    192:   /* Note that the source code is NULL character terminated. */
    193:   /* GL will automatically detect that therefore the length info can be 0 in this case (the last parameter) */
    194:   glShaderSource(vertexshader, 1, (const GLchar**)&vertexsource, 0);

    196:   /* Compile the vertex shader */
    197:   glCompileShader(vertexshader);
    198:   glGetShaderiv(vertexshader, GL_COMPILE_STATUS, &isCompiled_VS);
    199:   if (isCompiled_VS == GL_FALSE) {
    201:     int            maxLength;
    202:     char           *vertexInfoLog;
    203:     glGetShaderiv(vertexshader, GL_INFO_LOG_LENGTH, &maxLength);
    204:     PetscMalloc1(maxLength,&vertexInfoLog);
    205:     glGetShaderInfoLog(vertexshader, maxLength, &maxLength, vertexInfoLog);
    206:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"Failed to compile vertex shader %s",vertexInfoLog);
    207:   }

    209:   /* Create an empty fragment shader handle */
    210:   fragmentshader = glCreateShader(GL_FRAGMENT_SHADER);

    212:   /* Send the fragment shader source code to GL */
    213:   /* Note that the source code is NULL character terminated. */
    214:   /* GL will automatically detect that therefore the length info can be 0 in this case (the last parameter) */
    215:   glShaderSource(fragmentshader, 1, (const GLchar**)&fragmentsource, 0);

    217:   /* Compile the fragment shader */
    218:   glCompileShader(fragmentshader);
    219:   glGetShaderiv(fragmentshader, GL_COMPILE_STATUS, &isCompiled_FS);
    220:   if (isCompiled_FS == GL_FALSE) {
    222:     int            maxLength;
    223:     char           *fragmentInfoLog;
    224:     glGetShaderiv(fragmentshader, GL_INFO_LOG_LENGTH, &maxLength);
    225:     PetscMalloc1(maxLength,&fragmentInfoLog);
    226:     glGetShaderInfoLog(fragmentshader, maxLength, &maxLength, fragmentInfoLog);
    227:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"Failed to compile fragment shader %s",fragmentInfoLog);
    228:   }

    230:   /* If we reached this point it means the vertex and fragment shaders compiled and are syntax error free. */
    231:   /* We must link them together to make a GL shader program */
    232:   /* GL shader programs are monolithic. It is a single piece made of 1 vertex shader and 1 fragment shader. */
    233:   /* Assign our program handle a "name" */
    234:   shaderprogram = glCreateProgram();

    236:   /* Attach our shaders to our program */
    237:   glAttachShader(shaderprogram, vertexshader);
    238:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    239:   glAttachShader(shaderprogram, fragmentshader);
    240:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    242:   glBindAttribLocation(shaderprogram,0,"position");
    243:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    244:   glBindAttribLocation(shaderprogram,1,"color");
    245:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    247:   /* Link our program */
    248:   /* At this stage, the vertex and fragment programs are inspected, optimized and a binary code is generated for the shader. */
    249:   /* The binary code is uploaded to the GPU, if there is no error. */
    250:   glLinkProgram(shaderprogram);

    252:   /* Again, we must check and make sure that it linked. If it fails, it would mean either there is a mismatch between the vertex */
    253:   /* and fragment shaders. It might be that you have surpassed your GPU's abilities. Perhaps too many ALU operations or */
    254:   /* too many texel fetch instructions or too many interpolators or dynamic loops. */

    256:   glGetProgramiv(shaderprogram, GL_LINK_STATUS, &isLinked);
    257:   if (isLinked == GL_FALSE) {
    258:     /*
    259:     char          *shaderProgramInfoLog;
    260:     glGetProgramiv(shaderprogram, GL_INFO_LOG_LENGTH, &maxLength);
    261:     shaderProgramInfoLog = new char[maxLength];
    262:     glGetProgramInfoLog(shaderprogram, maxLength, &maxLength, shaderProgramInfoLog);
    263:     free(shaderProgramInfoLog);
    264:     */
    265:     SETERRQ(PETSC_COMM_SELF,PETSC_ERR_LIB,"Failed to compile fragment shader");
    266:   }

    268:   /* In your rendering code, you just need to call glUseProgram, call the various glUniform** to update your uniforms */
    269:   /* and then render. */
    270:   /* Load the shader into the rendering pipeline */
    271:   glUseProgram(shaderprogram);
    272:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    273:   return(0);
    274: }

    278: /*
    279:     This is currently all wrong, there is actually a separate shader for each window
    280:    so they cannot be stored as global
    281: */
    282: static PetscErrorCode FinalizeShader(void)
    283: {
    285:   /* When the user shuts down your program, you should deallocate all your GL resources. */
    286:   /* Unbind your shader. */
    287:   glUseProgram(0);
    288:   /* Let's detach */
    289:   glDetachShader(shaderprogram, vertexshader);
    290:   glDetachShader(shaderprogram, fragmentshader);
    291:   /* Delete the shaders */
    292:   glDeleteShader(vertexshader);
    293:   glDeleteShader(fragmentshader);
    294:   /* Delete the shader object */
    295:   glDeleteProgram(shaderprogram);
    296:   return(0);
    297: }

    299: PETSC_INTERN PetscErrorCode PetscDrawClear_OpenGL_Base(PetscDraw);

    301: #if defined(PETSC_HAVE_GLUT)
    302: #include <GLUT/glut.h>
    303: typedef struct {
    304:   int win;           /* OpenGL GLUT window identifier */
    305:   int x,y,w,h;       /* Size and location of window */
    306: } PetscDraw_OpenGL;

    308: static int currentwindow = -1;
    309: PETSC_STATIC_INLINE PetscErrorCode OpenGLWindow(PetscDraw_OpenGL *win)
    310: {
    311:   if (win->win == currentwindow) return 0;
    312:   currentwindow = win->win;
    313:   glutSetWindow(win->win);
    314:   return 0;
    315: }

    317: PETSC_STATIC_INLINE PetscErrorCode OpenGLString(float x,float y, const char *str,size_t len,int icolor)
    318: {
    319:   PetscInt i;

    321:   glColor3ub(rcolor[icolor],gcolor[icolor],bcolor[icolor]);
    322:   glRasterPos2f(x, y);
    323:   for (i = 0; i < len; i++) glutBitmapCharacter(GLUT_BITMAP_8_BY_13, str[i]);
    324:   return 0;
    325: }

    329: PetscErrorCode PetscDrawClear_OpenGL(PetscDraw draw)
    330: {

    334:   PetscDrawClear_OpenGL_Base(draw);
    335:   return(0);
    336: }

    340: static PetscErrorCode PetscDrawGetPopup_OpenGL(PetscDraw draw,PetscDraw *popup)
    341: {

    345:   PetscDrawCreate(PetscObjectComm((PetscObject)draw),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE,popup);
    346:   PetscDrawSetType(*popup,((PetscObject)draw)->type_name);

    348:   draw->popup = *popup;
    349:   return(0);
    350: }

    354: static PetscErrorCode PetscDrawStringVertical_OpenGL(PetscDraw draw,PetscReal x,PetscReal y,int c,const char chrs[])
    355: {
    356:   PetscErrorCode   ierr;
    357:   float            xx,yy;
    358:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    359:   PetscReal        tw,th;
    360:   size_t           i,n;

    363:   OpenGLWindow(win);
    364:   PetscStrlen(chrs,&n);
    365:   PetscDrawStringGetSize(draw,&tw,&th);
    366:   xx   = XTRANS(draw,x);
    367:   for (i=0; i<n; i++) {
    368:     yy   = YTRANS(draw,y-th*i);
    369:     OpenGLString(xx,yy,chrs+i,1,c);
    370:   }
    371:   return(0);
    372: }

    376: static PetscErrorCode PetscDrawString_OpenGL(PetscDraw draw,PetscReal x,PetscReal y,int c,const char chrs[])
    377: {
    378:   PetscErrorCode   ierr;
    379:   float            xx,yy;
    380:   size_t           len;
    381:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    382:   char             *substr;
    383:   PetscToken       token;

    386:   xx   = XTRANS(draw,x);
    387:   yy   = YTRANS(draw,y);
    388:   OpenGLWindow(win);

    390:   PetscTokenCreate(chrs,'\n',&token);
    391:   PetscTokenFind(token,&substr);
    392:   PetscStrlen(substr,&len);
    393:   OpenGLString(xx,yy,substr,len,c);
    394:   PetscTokenFind(token,&substr);
    395:   while (substr) {
    396:     yy  += 16;
    397:     PetscStrlen(substr,&len);
    398:     OpenGLString(xx,yy,substr,len,c);
    399:     PetscTokenFind(token,&substr);
    400:   }
    401:   PetscTokenDestroy(&token);
    402:   return(0);
    403: }

    407: static PetscErrorCode PetscDrawSetTitle_OpenGL(PetscDraw draw,const char title[])
    408: {
    409:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    410:   PetscErrorCode   ierr;

    413:   OpenGLWindow(win);
    414:   glutSetWindowTitle(title);
    415:   return(0);
    416: }

    420: static PetscErrorCode PetscDrawDestroy_OpenGL(PetscDraw draw)
    421: {
    422:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    423:   PetscErrorCode   ierr;

    426:   PetscDrawClear(draw);
    427:   PetscDrawDestroy(&draw->popup);
    428:   glutDestroyWindow(win->win);
    429:   PetscFree(draw->data);
    430:   return(0);
    431: }

    435: static PetscErrorCode PetscDrawFlush_OpenGL(PetscDraw draw)
    436: {
    437:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    438:   PetscErrorCode   ierr;

    441:   OpenGLWindow(win);
    442:   glutCheckLoop();
    443:   glFinish();
    444:   return(0);
    445: }

    449: static PetscErrorCode PetscDrawStringGetSize_OpenGL(PetscDraw draw,PetscReal *x,PetscReal  *y)
    450: {
    451:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    452:   PetscInt         w;
    453:   PetscErrorCode   ierr;

    456:   OpenGLWindow(win);
    457:   w    = glutBitmapWidth(GLUT_BITMAP_8_BY_13,'W');
    458:   if (x) *x   = w*(draw->coor_xr - draw->coor_xl)/((win->w)*(draw->port_xr - draw->port_xl));
    459:   if (y) *y   = (13./8.0)*w*(draw->coor_yr - draw->coor_yl)/((win->h)*(draw->port_yr - draw->port_yl));
    460:   return(0);
    461: }

    465: static PetscErrorCode PetscDrawResizeWindow_OpenGL(PetscDraw draw,int w,int h)
    466: {
    467:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    468:   PetscErrorCode   ierr;

    471:   OpenGLWindow(win);
    472:   glutReshapeWindow(w,h);
    473:   PetscDrawFlush(draw);
    474:   PetscDrawCheckResizedWindow(draw);
    475:   return(0);
    476: }

    478: static PetscBool resized = PETSC_FALSE;

    482: static PetscErrorCode PetscDrawCheckResizedWindow_OpenGL(PetscDraw draw)
    483: {

    487:   if (!resized) return(0);
    488:   resized = PETSC_FALSE;
    489:   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    490:   PetscDrawClear(draw);
    491:   return(0);
    492: }

    494: typedef struct {
    495:   int button,x,y;
    496: } OpenGLButton;
    497: static OpenGLButton Mouse;

    501: static PetscErrorCode PetscDrawGetMouseButton_OpenGL(PetscDraw draw,PetscDrawButton *button,PetscReal *x_user,PetscReal *y_user,PetscReal *x_phys,PetscReal *y_phys)
    502: {
    503:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    504:   int              px,py;

    507:   while (Mouse.button == -1) glutCheckLoop();

    509:   *button      = (PetscDrawButton)(Mouse.button + 1);
    510:   px           = Mouse.x;
    511:   py           = Mouse.y;
    512:   Mouse.button = -1;

    514:   if (x_phys) *x_phys = ((double)px)/((double)win->w);
    515:   if (y_phys) *y_phys = 1.0 - ((double)py)/((double)win->h);

    517:   if (x_user) *x_user = draw->coor_xl + ((((double)px)/((double)win->w)-draw->port_xl))*(draw->coor_xr - draw->coor_xl)/(draw->port_xr - draw->port_xl);
    518:   if (y_user) *y_user = draw->coor_yl + ((1.0 - ((double)py)/((double)win->h)-draw->port_yl))*(draw->coor_yr - draw->coor_yl)/(draw->port_yr - draw->port_yl);
    519:   return(0);
    520: }
    521: #elif defined(PETSC_HAVE_OPENGLES)
    522: typedef struct {
    523:   GLint   win;    /* not currently used */
    524:   int     w,h;    /* width and height in pixels */
    525:   int     view;
    526: } PetscDraw_OpenGL;

    528: static GLKView *globalGLKView[10] = {0,0,0,0,0,0,0,0,0,0};
    529: static int     globalGLKViewUsed[10]  = {0,0,0,0,0,0,0,0,0,0};
    530: PETSC_STATIC_INLINE PetscErrorCode OpenGLWindow(PetscDraw_OpenGL *win)
    531: {
    532:   return 0;
    533: }

    537: static PetscErrorCode PetscDrawClear_OpenGL(PetscDraw draw)
    538: {
    539:   PetscErrorCode   ierr;
    540:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;

    543:   /* remove all UIText added to window */
    544:   for (UIView *view in [globalGLKView[win->view] subviews]) {[view removeFromSuperview];}
    545:   PetscDrawClear_OpenGL_Base(draw);
    546:   return(0);
    547: }

    551: static PetscErrorCode PetscDrawGetPopup_OpenGL(PetscDraw draw,PetscDraw *popup)
    552: {

    556:   *popup = NULL;
    557:   return(0);
    558: }

    562: static PetscErrorCode PetscDrawString_OpenGL(PetscDraw draw,PetscReal x,PetscReal y,int c,const char chrs[])
    563: {
    564:   PetscErrorCode   ierr;
    565:   float            xx,yy;
    566:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    567:   UILabel          *yourLabel;

    570:   OpenGLWindow(win);
    571:   xx   = XPTRANS(draw,win,x);
    572:   yy   = YPTRANS(draw,win,y);
    573:   NSLog(@"Draw string start");
    574:   yourLabel = [[UILabel alloc] initWithFrame:CGRectMake(xx, yy, 300, 20)];
    575:   [yourLabel setTextColor:[UIColor colorWithRed:rcolor[c]/255.0 green:gcolor[c]/255.0 blue:rcolor[c]/255.0 alpha:1.0]];
    576:   [yourLabel setText: [[NSString alloc] initWithCString:chrs encoding:NSMacOSRomanStringEncoding]];
    577:   [yourLabel setBackgroundColor:[UIColor clearColor]];
    578:   /* [yourLabel setFont:[UIFont fontWithName: @"Trebuchet MS" size: 14.0f]]; */
    579:   [globalGLKView[win->view] addSubview:yourLabel];
    580:   NSLog(@"Draw string end");
    581:   return(0);
    582: }

    584: /*
    585:    I don't understand the rotation. It seems to maybe rotate from the middle of the width?

    587:    It would be nice if the frame could be made to match the text length automatically

    589:    This makes src/sys/draw/examples/tests/ex3.c look good but may be terrible for other locations
    590: */
    593: static PetscErrorCode PetscDrawStringVertical_OpenGL(PetscDraw draw,PetscReal x,PetscReal y,int c,const char chrs[])
    594: {
    595:   PetscErrorCode   ierr;
    596:   float            xx,yy, w = 100,h = 20;
    597:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    598:   UILabel          *yourLabel;

    601:   OpenGLWindow(win);
    602:   xx   = XPTRANS(draw,win,x);
    603:   yy   = YPTRANS(draw,win,y);
    604:   NSLog(@"Draw string vertical start");
    605:   yourLabel = [[UILabel alloc] initWithFrame:CGRectMake(0,0, w, h)];
    606:   [yourLabel setTextColor:[UIColor colorWithRed:rcolor[c]/255.0 green:gcolor[c]/255.0 blue:rcolor[c]/255.0 alpha:1.0]];
    607:   [yourLabel setText: [[NSString alloc] initWithCString:chrs encoding:NSMacOSRomanStringEncoding]];
    608:   [yourLabel setBackgroundColor:[UIColor clearColor]];
    609:   [yourLabel setTransform:CGAffineTransformTranslate(CGAffineTransformMakeRotation(-PETSC_PI / 2),-w/2.0-yy,-h+xx)];
    610:   /* [yourLabel setFont:[UIFont fontWithName: @"Trebuchet MS" size: 14.0f]]; */
    611:   [globalGLKView[win->view] addSubview:yourLabel];
    612:   NSLog(@"Draw string vertical end");
    613:   return(0);
    614: }

    618: static PetscErrorCode PetscDrawSetTitle_OpenGL(PetscDraw draw,const char title[])
    619: {
    620:   return 0;
    621: }
    624: static PetscErrorCode PetscDrawDestroy_OpenGL(PetscDraw draw)
    625: {
    626:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    627:   PetscErrorCode   ierr;
    628:   PetscInt         i;

    631:   globalGLKViewUsed[win->view] = 0;
    632:   PetscFree(draw->data);
    633:   return(0);
    634:   return(0);
    635: }
    638: static PetscErrorCode PetscDrawFlush_OpenGL(PetscDraw draw)
    639: {
    640:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;

    642:   GLenum err;
    643:   glFlush();
    644:   err = glGetError();
    645:   if (err != GL_NO_ERROR) {
    646:     NSLog(@"GL error detected glFlush()");
    647:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Unable to flush OpenGL Error Code %d",err);
    648:   }
    649:   [globalGLKView[win->view] display];
    650:   NSLog(@"Completed display in PetscDrawFlush()");
    651:   return 0;
    652: }
    655: static PetscErrorCode PetscDrawStringGetSize_OpenGL(PetscDraw draw,PetscReal *x,PetscReal  *y)
    656: {
    657:   float w = .02;
    658:   if (x) *x = w*(draw->coor_xr - draw->coor_xl)/(draw->port_xr - draw->port_xl);
    659:   if (y) *y = (13./8.0)*w*(draw->coor_yr - draw->coor_yl)/(draw->port_yr - draw->port_yl);
    660:   return 0;
    661: }
    664: static PetscErrorCode PetscDrawResizeWindow_OpenGL(PetscDraw draw,int w,int h)
    665: {
    666:   return 0;
    667: }
    670: static PetscErrorCode PetscDrawCheckResizedWindow_OpenGL(PetscDraw draw)
    671: {
    672:   return 0;
    673: }
    676: static PetscErrorCode PetscDrawGetMouseButton_OpenGL(PetscDraw draw,PetscDrawButton *button,PetscReal *x_user,PetscReal *y_user,PetscReal *x_phys,PetscReal *y_phys)
    677: {
    678:   return 0;
    679: }
    680: #endif

    682: /* -----------------------------------------------------------------------*/

    686: PetscErrorCode PetscDrawClear_OpenGL_Base(PetscDraw draw)
    687: {
    688:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    689:   PetscErrorCode   ierr;
    690:   float            xl,yl,xr,yr;
    691:   GLfloat          vertices[12];
    692:   GLfloat          colors[18];
    693:   GLuint           positionBufferObject;
    694:   GLuint           colorBufferObject;
    695:   GLenum           err;

    698:   OpenGLWindow(win);
    699:   xl   = -1.0 + 2.0*((draw)->port_xl);
    700:   xr   = -1.0 + 2.0*((draw)->port_xr);
    701:   yl   = -1.0 + 2.0*((draw)->port_yl);
    702:   yr   = -1.0 + 2.0*((draw)->port_yr);

    704:   vertices[0] = xl;
    705:   vertices[1] = yl;
    706:   vertices[2] = xr;
    707:   vertices[3] = yl;
    708:   vertices[4] = xl;
    709:   vertices[5] = yr;

    711:   vertices[6]  = xl;
    712:   vertices[7]  = yr;
    713:   vertices[8]  = xr;
    714:   vertices[9]  = yr;
    715:   vertices[10] = xr;
    716:   vertices[11] = yl;

    718:   colors[0] = 1.0;  colors[1] = 1.0; colors[2] = 1.0;
    719:   colors[3] = 1.0;  colors[4] = 1.0; colors[5] = 1.0;
    720:   colors[6] = 1.0;  colors[7] = 1.0; colors[8] = 1.0;

    722:   colors[9]  = 1.0;  colors[10] = 1.0; colors[11] = 1.0;
    723:   colors[12] = 1.0;  colors[13] = 1.0; colors[14] = 1.0;
    724:   colors[15] = 1.0;  colors[16] = 1.0; colors[17] = 1.0;

    726:   glGenBuffers(1, &positionBufferObject);
    727:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    728:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    729:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    730:   glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    731:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    732:   glEnableVertexAttribArray(0);
    733:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    734:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    735:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    737:   glGenBuffers(1, &colorBufferObject);
    738:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    739:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    740:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    741:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    742:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    743:   glEnableVertexAttribArray(1);
    744:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    745:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    746:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    748:   glDrawArrays(GL_TRIANGLES, 0, 6);
    749:   glDisableVertexAttribArray(0);
    750:   glDisableVertexAttribArray(1);
    751:   glDeleteBuffers(1, &positionBufferObject);
    752:   glDeleteBuffers(1, &colorBufferObject);
    753:   PetscDrawFlush(draw);
    754:   return(0);
    755: }

    759: static PetscErrorCode PetscDrawPoint_OpenGL(PetscDraw draw,PetscReal xl,PetscReal yl,int cl)
    760: {
    761:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    762:   GLfloat          vertices[2],colors[3];
    763:   PetscErrorCode   ierr;
    764:   GLuint           positionBufferObject;
    765:   GLuint           colorBufferObject;
    766:   GLenum           err;

    769:   vertices[0] = XTRANS(draw,xl);
    770:   vertices[1] = YTRANS(draw,yl);
    771:   colors[0]   = rcolor[cl]/255.0;  colors[1] = gcolor[cl]/255.0; colors[2] = bcolor[cl]/255.0;

    773:   OpenGLWindow(win);
    774:   glGenBuffers(1, &positionBufferObject);
    775:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    776:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    777:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    778:   glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    779:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    780:   glEnableVertexAttribArray(0);
    781:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    782:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    783:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    785:   glGenBuffers(1, &colorBufferObject);
    786:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    787:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    788:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    789:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    790:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    791:   glEnableVertexAttribArray(1);
    792:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    793:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    794:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    796:   glDrawArrays(GL_POINTS, 0, 2);
    797:   glDisableVertexAttribArray(0);
    798:   glDisableVertexAttribArray(1);
    799:   glDeleteBuffers(1, &positionBufferObject);
    800:   glDeleteBuffers(1, &colorBufferObject);
    801:   return(0);
    802: }

    806: static PetscErrorCode PetscDrawLine_OpenGL(PetscDraw draw,PetscReal xl,PetscReal yl,PetscReal xr,PetscReal yr,int cl)
    807: {
    808:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    809:   GLfloat          linevertices[4],colors[6];
    810:   PetscErrorCode   ierr;
    811:   GLenum           err;
    812:   GLuint           positionBufferObject;
    813:   GLuint           colorBufferObject;

    817:   linevertices[0] = XTRANS(draw,xl);
    818:   linevertices[2] = XTRANS(draw,xr);
    819:   linevertices[1] = YTRANS(draw,yl);
    820:   linevertices[3] = YTRANS(draw,yr);
    821:   if (linevertices[0] == linevertices[2] && linevertices[1] == linevertices[3]) return(0);
    822:   colors[0] = rcolor[cl]/255.0;  colors[1] = gcolor[cl]/255.0; colors[2] = bcolor[cl]/255.0;
    823:   colors[3] = rcolor[cl]/255.0;  colors[4] = gcolor[cl]/255.0; colors[5] = bcolor[cl]/255.0;

    825:   OpenGLWindow(win);
    826:   /* http://arcsynthesis.org/gltut/Basics/Tutorial%2001.html */
    827:   glGenBuffers(1, &positionBufferObject);
    828:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    829:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    830:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    831:   glBufferData(GL_ARRAY_BUFFER, sizeof(linevertices), linevertices, GL_STATIC_DRAW);
    832:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    833:   glEnableVertexAttribArray(0);
    834:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    835:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    836:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    838:   glGenBuffers(1, &colorBufferObject);
    839:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    840:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    841:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    842:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    843:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    844:   glEnableVertexAttribArray(1);
    845:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    846:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    847:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    849:   glDrawArrays(GL_LINES, 0, 2);
    850:   glDisableVertexAttribArray(0);
    851:   glDisableVertexAttribArray(1);
    852:   glDeleteBuffers(1, &positionBufferObject);
    853:   glDeleteBuffers(1, &colorBufferObject);
    854:   return(0);
    855: }

    859: static PetscErrorCode PetscDrawTriangle_OpenGL(PetscDraw draw,PetscReal X1,PetscReal Y_1,PetscReal X2,PetscReal Y2,PetscReal X3,PetscReal Y3,int c1,int c2,int c3)
    860: {
    861:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    862:   PetscErrorCode   ierr;
    863:   GLfloat          vertices[6],colors[9];
    864:   GLenum           err;
    865:   GLuint           positionBufferObject;
    866:   GLuint           colorBufferObject;

    869:   vertices[0] = XTRANS(draw,X1);
    870:   vertices[1] = YTRANS(draw,Y_1);
    871:   vertices[2] = XTRANS(draw,X2);
    872:   vertices[3] = YTRANS(draw,Y2);
    873:   vertices[4] = XTRANS(draw,X3);
    874:   vertices[5] = YTRANS(draw,Y3);
    875:   colors[0]   = rcolor[c1]/255.0;  colors[1] = gcolor[c1]/255.0; colors[2] = bcolor[c1]/255.0;
    876:   colors[3]   = rcolor[c2]/255.0;  colors[4] = gcolor[c2]/255.0; colors[5] = bcolor[c2]/255.0;
    877:   colors[6]   = rcolor[c3]/255.0;  colors[7] = gcolor[c3]/255.0; colors[8] = bcolor[c3]/255.0;

    879:   OpenGLWindow(win);
    880:   glGenBuffers(1, &positionBufferObject);
    881:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    882:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    883:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    884:   glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    885:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    886:   glEnableVertexAttribArray(0);
    887:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    888:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    889:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    891:   glGenBuffers(1, &colorBufferObject);
    892:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    893:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    894:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    895:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    896:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    897:   glEnableVertexAttribArray(1);
    898:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    899:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    900:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    902:   glDrawArrays(GL_TRIANGLES, 0, 3);
    903:   glDisableVertexAttribArray(0);
    904:   glDisableVertexAttribArray(1);
    905:   glDeleteBuffers(1, &positionBufferObject);
    906:   glDeleteBuffers(1, &colorBufferObject);
    907:   return(0);
    908: }

    912: static PetscErrorCode PetscDrawRectangle_OpenGL(PetscDraw draw,PetscReal Xl,PetscReal Yl,PetscReal Xr,PetscReal Yr,int c1,int c2,int c3,int c4)
    913: {
    914:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    915:   PetscErrorCode   ierr;
    916:   GLfloat          vertices[12],colors[18];
    917:   float            x1,y_1,x2,y2;
    918:   GLuint           positionBufferObject;
    919:   GLuint           colorBufferObject;
    920:   GLenum           err;

    923:   x1  = XTRANS(draw,Xl);
    924:   y_1 = YTRANS(draw,Yl);
    925:   x2  = XTRANS(draw,Xr);
    926:   y2  = YTRANS(draw,Yr);

    928:   OpenGLWindow(win);

    930:   vertices[0] = x1; colors[0] = rcolor[c1]/255.0;  colors[1] = gcolor[c1]/255.0; colors[2] = bcolor[c1]/255.0;
    931:   vertices[1] = y_1;
    932:   vertices[2] = x2;colors[3] = rcolor[c2]/255.0;  colors[4] = gcolor[c2]/255.0; colors[5] = bcolor[c2]/255.0;
    933:   vertices[3] = y_1;
    934:   vertices[4] = x1;colors[6] = rcolor[c4]/255.0;  colors[7] = gcolor[c4]/255.0; colors[8] = bcolor[c4]/255.0;
    935:   vertices[5] = y2;

    937:   vertices[6]  = x1;colors[9] = rcolor[c4]/255.0;  colors[10] = gcolor[c4]/255.0; colors[11] = bcolor[c4]/255.0;
    938:   vertices[7]  = y2;
    939:   vertices[8]  = x2;colors[12] = rcolor[c3]/255.0;  colors[13] = gcolor[c3]/255.0; colors[14] = bcolor[c3]/255.0;
    940:   vertices[9]  = y2;
    941:   vertices[10] = x2;colors[15] = rcolor[c2]/255.0;  colors[16] = gcolor[c2]/255.0; colors[17] = bcolor[c2]/255.0;
    942:   vertices[11] = y_1;

    944:   glGenBuffers(1, &positionBufferObject);
    945:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    946:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    947:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    948:   glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    949:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    950:   glEnableVertexAttribArray(0);
    951:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    952:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    953:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    955:   glGenBuffers(1, &colorBufferObject);
    956:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    957:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    958:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    959:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    960:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    961:   glEnableVertexAttribArray(1);
    962:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    963:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    964:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    966:   glDrawArrays(GL_TRIANGLES, 0, 6);
    967:   glDisableVertexAttribArray(0);
    968:   glDisableVertexAttribArray(1);
    969:   glDeleteBuffers(1, &positionBufferObject);
    970:   glDeleteBuffers(1, &colorBufferObject);
    971:   return(0);
    972: }

    977: static PetscErrorCode PetscDrawPause_OpenGL(PetscDraw draw)
    978: {

    982:   if (draw->pause > 0) PetscSleep(draw->pause);
    983:   else if (draw->pause == -1) {
    984:     PetscDrawButton button = PETSC_BUTTON_NONE;
    985:     PetscDrawGetMouseButton(draw,&button,0,0,0,0);
    986:     if (button == PETSC_BUTTON_CENTER) draw->pause = 0;
    987:   }
    988:   return(0);
    989: }

    992: static struct _PetscDrawOps DvOps = { 0,
    993:                                       PetscDrawFlush_OpenGL,
    994:                                       PetscDrawLine_OpenGL,
    995:                                       0,
    996:                                       0,
    997:                                       PetscDrawPoint_OpenGL,
    998:                                       0,
    999:                                       PetscDrawString_OpenGL,
    1000:                                       PetscDrawStringVertical_OpenGL,
    1001:                                       0, /* PetscDrawStringSetSize_OpenGL,*/
    1002:                                       PetscDrawStringGetSize_OpenGL,
    1003:                                       0, /* PetscDrawSetViewport_OpenGL,*/
    1004:                                       PetscDrawClear_OpenGL,
    1005:                                       PetscDrawRectangle_OpenGL,
    1006:                                       PetscDrawTriangle_OpenGL,
    1007:                                       0, /* PetscDrawEllipse_OpenGL,*/
    1008:                                       PetscDrawGetMouseButton_OpenGL,
    1009:                                       PetscDrawPause_OpenGL,
    1010:                                       0,
    1011:                                       0,
    1012:                                       PetscDrawGetPopup_OpenGL,
    1013:                                       PetscDrawSetTitle_OpenGL,
    1014:                                       PetscDrawCheckResizedWindow_OpenGL,
    1015:                                       PetscDrawResizeWindow_OpenGL,
    1016:                                       PetscDrawDestroy_OpenGL,
    1017:                                       0,
    1018:                                       0, /* PetscDrawGetSingleton_OpenGL,*/
    1019:                                       0, /* PetscDrawRestoreSingleton_OpenGL,*/
    1020:                                       0,
    1021:                                       0,
    1022:                                       0,
    1023:                                       PetscDrawLine_OpenGL};

    1025: #if defined(PETSC_HAVE_GLUT)
    1026: /* callbacks required by GLUT */
    1027: static void display(void) {;}
    1028: static void reshape(int width, int height)
    1029: {
    1030:   glViewport(0, 0, width, height);
    1031:   resized = PETSC_TRUE;
    1032: }
    1033: static void mouse(int button, int state,int x, int y)
    1034: {
    1035:   if (state == GLUT_UP) {
    1036:     Mouse.button = button;
    1037:     Mouse.x      = x;
    1038:     Mouse.y      = y;
    1039:   }
    1040: }

    1044: PETSC_EXTERN PetscErrorCode PetscDrawCreate_GLUT(PetscDraw draw)
    1045: {
    1046:   PetscDraw_OpenGL *win;
    1047:   PetscErrorCode   ierr;
    1048:   PetscInt         xywh[4],osize = 4;
    1049:   int              x = draw->x,y = draw->y,w = draw->w,h = draw->h;
    1050:   static int       xavailable = 0,yavailable = 0,xmax = 0,ymax = 0,ybottom = 0;
    1051:   static PetscBool initialized = PETSC_FALSE;
    1052:   int              argc;
    1053:   char             **argv;

    1056:   if (!initialized) {
    1057:     PetscGetArgs(&argc,&argv);
    1058:     glutInit(&argc, argv);
    1059:     glutInitDisplayMode(GLUT_RGBA /* | GLUT_DOUBLE */| GLUT_DEPTH);
    1060:     InitializeColors();
    1061:   }

    1063:   /*
    1064:       Initialize the display size
    1065:   */
    1066:   if (!xmax) {
    1067:     xmax = glutGet(GLUT_SCREEN_WIDTH);
    1068:     ymax = glutGet(GLUT_SCREEN_HEIGHT);
    1069:   }

    1071:   if (w == PETSC_DECIDE) w = draw->w = 300;
    1072:   if (h == PETSC_DECIDE) h = draw->h = 300;
    1073:   switch (w) {
    1074:   case PETSC_DRAW_FULL_SIZE: w = draw->w = xmax - 10; break;
    1075:   case PETSC_DRAW_HALF_SIZE: w = draw->w = (xmax - 20)/2; break;
    1076:   case PETSC_DRAW_THIRD_SIZE: w = draw->w = (xmax - 30)/3; break;
    1077:   case PETSC_DRAW_QUARTER_SIZE: w = draw->w = (xmax - 40)/4; break;
    1078:   }
    1079:   switch (h) {
    1080:   case PETSC_DRAW_FULL_SIZE: h = draw->h = ymax - 10; break;
    1081:   case PETSC_DRAW_HALF_SIZE: h = draw->h = (ymax - 20)/2; break;
    1082:   case PETSC_DRAW_THIRD_SIZE: h = draw->h = (ymax - 30)/3; break;
    1083:   case PETSC_DRAW_QUARTER_SIZE: h = draw->h = (ymax - 40)/4; break;
    1084:   }

    1086:   /* allow user to set location and size of window */
    1087:   xywh[0] = x; xywh[1] = y; xywh[2] = w; xywh[3] = h;
    1088:   PetscOptionsGetIntArray(NULL,"-geometry",xywh,&osize,NULL);
    1089:   x       = (int) xywh[0]; y = (int) xywh[1]; w = (int) xywh[2]; h = (int) xywh[3];

    1092:   if (draw->x == PETSC_DECIDE || draw->y == PETSC_DECIDE) {
    1093:     /*
    1094:        PETSc tries to place windows starting in the upper left corner and
    1095:        moving across to the right.

    1097:               --------------------------------------------
    1098:               |  Region used so far +xavailable,yavailable |
    1099:               |                     +                      |
    1100:               |                     +                      |
    1101:               |++++++++++++++++++++++ybottom               |
    1102:               |                                            |
    1103:               |                                            |
    1104:               |--------------------------------------------|
    1105:     */
    1106:     /*  First: can we add it to the right? */
    1107:     if (xavailable+w+10 <= xmax) {
    1108:       x       = xavailable;
    1109:       y       = yavailable;
    1110:       ybottom = PetscMax(ybottom,y + h + 30);
    1111:     } else {
    1112:       /* No, so add it below on the left */
    1113:       xavailable = 0;
    1114:       x          = 0;
    1115:       yavailable = ybottom;
    1116:       y          = ybottom;
    1117:       ybottom    = ybottom + h + 30;
    1118:     }
    1119:   }
    1120:   /* update available region */
    1121:   xavailable = PetscMax(xavailable,x + w + 10);
    1122:   if (xavailable >= xmax) {
    1123:     xavailable = 0;
    1124:     yavailable = yavailable + h + 30;
    1125:     ybottom    = yavailable;
    1126:   }
    1127:   if (yavailable >= ymax) {
    1128:     y          = 0;
    1129:     yavailable = 0;
    1130:     ybottom    = 0;
    1131:   }

    1133:   PetscMemcpy(draw->ops,&DvOps,sizeof(DvOps));

    1135:   /* actually create and open the window */
    1136:   PetscNew(&win);
    1137:   PetscLogObjectMemory((PetscObject)draw,sizeof(PetscDraw_OpenGL));

    1139:   if (x < 0 || y < 0)   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative corner of window");
    1140:   if (w <= 0 || h <= 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative window width or height");

    1142:   win->x = x;
    1143:   win->y = y;
    1144:   win->w = w;
    1145:   win->h = h;

    1147:   glutInitWindowSize(w, h);
    1148:   glutInitWindowPosition(x,y);
    1149:   win->win = glutCreateWindow(draw->title);
    1150:   glutDisplayFunc(display);
    1151:   glutReshapeFunc(reshape);
    1152:   Mouse.button = -1;
    1153:   Mouse.x      = -1;
    1154:   Mouse.y      = -1;
    1155:   glutMouseFunc(mouse);

    1157:   glClearColor(1.0,1.0,1.0,1.0);

    1159:   draw->data = win;
    1160:   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    1161:   InitializeShader();

    1163:   PetscDrawClear(draw);
    1164:   resized = PETSC_FALSE; /* opening the window triggers OpenGL call to reshape so need to cancel that resized flag */
    1165:   glutCheckLoop();
    1166:   return(0);
    1167: }

    1171: /*@C
    1172:    PetscDrawOpenGLUT - Opens an OpenGL window based on GLUT for use with the PetscDraw routines.

    1174:    Collective on MPI_Comm

    1176:    Input Parameters:
    1177: +  comm - the communicator that will share X-window
    1178: .  display - the X display on which to open,or null for the local machine
    1179: .  title - the title to put in the title bar,or null for no title
    1180: .  x,y - the screen coordinates of the upper left corner of window
    1181:           may use PETSC_DECIDE for these two arguments, then PETSc places the
    1182:           window
    1183: -  w, h - the screen width and height in pixels,  or PETSC_DRAW_HALF_SIZE, PETSC_DRAW_FULL_SIZE,
    1184:           or PETSC_DRAW_THIRD_SIZE or PETSC_DRAW_QUARTER_SIZE

    1186:    Output Parameters:
    1187: .  draw - the drawing context.

    1189:    Options Database Keys:
    1190: +  -nox - Disables all x-windows output
    1191: .  -draw_pause <pause> - Sets time (in seconds) that the
    1192:        program pauses after PetscDrawPause() has been called
    1193:        (0 is default, -1 implies until user input).
    1194: .  -draw_cmap <name> - Sets the colormap to use.
    1195: .  -draw_cmap_reverse - Reverses the colormap.
    1196: -  -draw_cmap_brighten - Brighten (0 < beta < 1) or darken (-1 < beta < 0) the colormap.

    1198:    Level: beginner

    1200:    Note:
    1201:    When finished with the drawing context, it should be destroyed
    1202:    with PetscDrawDestroy().

    1204:    Note for Fortran Programmers:
    1205:    Whenever indicating null character data in a Fortran code,
    1206:    NULL_CHARACTER must be employed; using NULL is not
    1207:    correct for character data!  Thus, NULL_CHARACTER can be
    1208:    used for the display and title input parameters.

    1210:    Concepts: OpenGL^drawing to

    1212: .seealso: PetscDrawFlush(), PetscDrawDestroy(), PetscDrawOpenX(), PetscDrawCreate()
    1213: @*/
    1214: PetscErrorCode  PetscDrawOpenGLUT(MPI_Comm comm,const char display[],const char title[],int x,int y,int w,int h,PetscDraw *draw)
    1215: {

    1219:   PetscDrawCreate(comm,display,title,x,y,w,h,draw);
    1220:   PetscDrawSetType(*draw,PETSC_DRAW_GLUT);
    1221:   return(0);
    1222: }

    1224: #elif defined(PETSC_HAVE_OPENGLES)

    1228: PetscErrorCode  PetscDrawOpenGLESRegisterGLKView(GLKView *view)
    1229: {
    1230:   PetscInt i;

    1233:   for (i=0; i<10; i++) {
    1234:     if (view == globalGLKView[i]) return(0);  /* already registered */
    1235:     if (!globalGLKView[i]) {
    1236:       globalGLKView[i] = view;
    1237:       return(0);
    1238:     }
    1239:   }
    1240:   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Out of GLKView slots");
    1241:   return(0);
    1242: }

    1246: PETSC_EXTERN PetscErrorCode PetscDrawCreate_OpenGLES(PetscDraw draw)
    1247: {
    1248:   PetscDraw_OpenGL *win;
    1249:   PetscErrorCode   ierr;
    1250:   static PetscBool initialized = PETSC_FALSE;
    1251:   PetscInt         i;

    1254:   NSLog(@"Beginning PetscDrawCreate_OpenGLES()");

    1256:   PetscMemcpy(draw->ops,&DvOps,sizeof(DvOps));
    1257:   PetscNew(&win);
    1258:   PetscLogObjectMemory((PetscObject)draw,sizeof(PetscDraw_OpenGL));

    1260:   draw->data = win;
    1261:   win->view  = -1;
    1262:   for (i=0; i<10; i++) {
    1263:     if (!globalGLKViewUsed[i]) {
    1264:       win->view = i;
    1265:       win->w    = globalGLKView[win->view].frame.size.width;
    1266:       win->h    = globalGLKView[win->view].frame.size.height;
    1267:       [globalGLKView[win->view] bindDrawable];
    1268:       globalGLKViewUsed[i] = 1;
    1269:       break;
    1270:     }
    1271:   }
    1272:   if (win->view == -1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Requested more OpenGL ES windows then provided with PetscDrawOpenGLRegisterGLKView()");

    1274:   if (!initialized) {
    1275:     initialized = PETSC_TRUE;
    1276:     InitializeColors();
    1277:   }
    1278:   InitializeShader();

    1280:   PetscDrawClear(draw);
    1281:   NSLog(@"Ending PetscDrawCreate_OpenGLES()");
    1282:   return(0);
    1283: }

    1285: #endif