/* * Mesa 3-D graphics library * * Copyright (C) 1999-2007 Brian Paul All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. */ /** * \file xm_api.c * * All the XMesa* API functions. * * * NOTES: * * The window coordinate system origin (0,0) is in the lower-left corner * of the window. X11's window coordinate origin is in the upper-left * corner of the window. Therefore, most drawing functions in this * file have to flip Y coordinates. * * Define USE_XSHM in the Makefile with -DUSE_XSHM if you want to compile * in support for the MIT Shared Memory extension. If enabled, when you * use an Ximage for the back buffer in double buffered mode, the "swap" * operation will be faster. You must also link with -lXext. * * Byte swapping: If the Mesa host and the X display use a different * byte order then there's some trickiness to be aware of when using * XImages. The byte ordering used for the XImage is that of the X * display, not the Mesa host. * The color-to-pixel encoding for True/DirectColor must be done * according to the display's visual red_mask, green_mask, and blue_mask. * If XPutPixel is used to put a pixel into an XImage then XPutPixel will * do byte swapping if needed. If one wants to directly "poke" the pixel * into the XImage's buffer then the pixel must be byte swapped first. In * Mesa, when byte swapping is needed we use the PF_TRUECOLOR pixel format * and use XPutPixel everywhere except in the implementation of * glClear(GL_COLOR_BUFFER_BIT). We want this function to be fast so * instead of using XPutPixel we "poke" our values after byte-swapping * the clear pixel value if needed. * */ #ifdef __CYGWIN__ #undef WIN32 #undef __WIN32__ #endif #include "glxheader.h" #include "xmesaP.h" #include "main/api_exec.h" #include "main/context.h" #include "main/extensions.h" #include "main/framebuffer.h" #include "main/imports.h" #include "main/macros.h" #include "main/renderbuffer.h" #include "main/teximage.h" #include "main/version.h" #include "main/vtxfmt.h" #include "swrast/swrast.h" #include "swrast/s_renderbuffer.h" #include "swrast_setup/swrast_setup.h" #include "vbo/vbo.h" #include "tnl/tnl.h" #include "tnl/t_context.h" #include "tnl/t_pipeline.h" #include "drivers/common/driverfuncs.h" #include "drivers/common/meta.h" /** * Global X driver lock */ mtx_t _xmesa_lock; /**********************************************************************/ /***** X Utility Functions *****/ /**********************************************************************/ /** * Return the host's byte order as LSBFirst or MSBFirst ala X. */ static int host_byte_order( void ) { int i = 1; char *cptr = (char *) &i; return (*cptr==1) ? LSBFirst : MSBFirst; } /** * Check if the X Shared Memory extension is available. * Return: 0 = not available * 1 = shared XImage support available * 2 = shared Pixmap support available also */ static int check_for_xshm( XMesaDisplay *display ) { #if defined(USE_XSHM) int ignore; if (XQueryExtension( display, "MIT-SHM", &ignore, &ignore, &ignore )) { /* Note: we're no longer calling XShmQueryVersion() here. It seems * to be flakey (triggers a spurious X protocol error when we close * one display connection and start using a new one. XShm has been * around a long time and hasn't changed so if MIT_SHM is supported * we assume we're good to go. */ return 2; } else { return 0; } #else /* No XSHM support */ return 0; #endif } /** * Apply gamma correction to an intensity value in [0..max]. Return the * new intensity value. */ static GLint gamma_adjust( GLfloat gamma, GLint value, GLint max ) { if (gamma == 1.0) { return value; } else { double x = (double) value / (double) max; return IROUND_POS((GLfloat) max * pow(x, 1.0F/gamma)); } } /** * Return the true number of bits per pixel for XImages. * For example, if we request a 24-bit deep visual we may actually need/get * 32bpp XImages. This function returns the appropriate bpp. * Input: dpy - the X display * visinfo - desribes the visual to be used for XImages * Return: true number of bits per pixel for XImages */ static int bits_per_pixel( XMesaVisual xmv ) { XMesaDisplay *dpy = xmv->display; XMesaVisualInfo visinfo = xmv->visinfo; XMesaImage *img; int bitsPerPixel; /* Create a temporary XImage */ img = XCreateImage( dpy, visinfo->visual, visinfo->depth, ZPixmap, 0, /*format, offset*/ malloc(8), /*data*/ 1, 1, /*width, height*/ 32, /*bitmap_pad*/ 0 /*bytes_per_line*/ ); assert(img); /* grab the bits/pixel value */ bitsPerPixel = img->bits_per_pixel; /* free the XImage */ free( img->data ); img->data = NULL; XMesaDestroyImage( img ); return bitsPerPixel; } /* * Determine if a given X window ID is valid (window exists). * Do this by calling XGetWindowAttributes() for the window and * checking if we catch an X error. * Input: dpy - the display * win - the window to check for existance * Return: GL_TRUE - window exists * GL_FALSE - window doesn't exist */ static GLboolean WindowExistsFlag; static int window_exists_err_handler( XMesaDisplay* dpy, XErrorEvent* xerr ) { (void) dpy; if (xerr->error_code == BadWindow) { WindowExistsFlag = GL_FALSE; } return 0; } static GLboolean window_exists( XMesaDisplay *dpy, Window win ) { XWindowAttributes wa; int (*old_handler)( XMesaDisplay*, XErrorEvent* ); WindowExistsFlag = GL_TRUE; old_handler = XSetErrorHandler(window_exists_err_handler); XGetWindowAttributes( dpy, win, &wa ); /* dummy request */ XSetErrorHandler(old_handler); return WindowExistsFlag; } static Status get_drawable_size( XMesaDisplay *dpy, Drawable d, GLuint *width, GLuint *height ) { Window root; Status stat; int xpos, ypos; unsigned int w, h, bw, depth; stat = XGetGeometry(dpy, d, &root, &xpos, &ypos, &w, &h, &bw, &depth); *width = w; *height = h; return stat; } /** * Return the size of the window (or pixmap) that corresponds to the * given XMesaBuffer. * \param width returns width in pixels * \param height returns height in pixels */ void xmesa_get_window_size(XMesaDisplay *dpy, XMesaBuffer b, GLuint *width, GLuint *height) { Status stat; mtx_lock(&_xmesa_lock); XSync(b->xm_visual->display, 0); /* added for Chromium */ stat = get_drawable_size(dpy, b->frontxrb->pixmap, width, height); mtx_unlock(&_xmesa_lock); if (!stat) { /* probably querying a window that's recently been destroyed */ _mesa_warning(NULL, "XGetGeometry failed!\n"); *width = *height = 1; } } /**********************************************************************/ /***** Linked list of XMesaBuffers *****/ /**********************************************************************/ XMesaBuffer XMesaBufferList = NULL; /** * Allocate a new XMesaBuffer object which corresponds to the given drawable. * Note that XMesaBuffer is derived from struct gl_framebuffer. * The new XMesaBuffer will not have any size (Width=Height=0). * * \param d the corresponding X drawable (window or pixmap) * \param type either WINDOW, PIXMAP or PBUFFER, describing d * \param vis the buffer's visual * \param cmap the window's colormap, if known. * \return new XMesaBuffer or NULL if any problem */ static XMesaBuffer create_xmesa_buffer(XMesaDrawable d, BufferType type, XMesaVisual vis, XMesaColormap cmap) { XMesaBuffer b; assert(type == WINDOW || type == PIXMAP || type == PBUFFER); b = (XMesaBuffer) CALLOC_STRUCT(xmesa_buffer); if (!b) return NULL; b->display = vis->display; b->xm_visual = vis; b->type = type; b->cmap = cmap; _mesa_initialize_window_framebuffer(&b->mesa_buffer, &vis->mesa_visual); b->mesa_buffer.Delete = xmesa_delete_framebuffer; /* * Front renderbuffer */ b->frontxrb = xmesa_new_renderbuffer(NULL, 0, vis, GL_FALSE); if (!b->frontxrb) { free(b); return NULL; } b->frontxrb->Parent = b; b->frontxrb->drawable = d; b->frontxrb->pixmap = (XMesaPixmap) d; _mesa_add_renderbuffer(&b->mesa_buffer, BUFFER_FRONT_LEFT, &b->frontxrb->Base.Base); /* * Back renderbuffer */ if (vis->mesa_visual.doubleBufferMode) { b->backxrb = xmesa_new_renderbuffer(NULL, 0, vis, GL_TRUE); if (!b->backxrb) { /* XXX free front xrb too */ free(b); return NULL; } b->backxrb->Parent = b; /* determine back buffer implementation */ b->db_mode = vis->ximage_flag ? BACK_XIMAGE : BACK_PIXMAP; _mesa_add_renderbuffer(&b->mesa_buffer, BUFFER_BACK_LEFT, &b->backxrb->Base.Base); } /* * Other renderbuffer (depth, stencil, etc) */ _swrast_add_soft_renderbuffers(&b->mesa_buffer, GL_FALSE, /* color */ vis->mesa_visual.haveDepthBuffer, vis->mesa_visual.haveStencilBuffer, vis->mesa_visual.haveAccumBuffer, GL_FALSE, /* software alpha buffer */ vis->mesa_visual.numAuxBuffers > 0 ); /* GLX_EXT_texture_from_pixmap */ b->TextureTarget = 0; b->TextureFormat = GLX_TEXTURE_FORMAT_NONE_EXT; b->TextureMipmap = 0; /* insert buffer into linked list */ b->Next = XMesaBufferList; XMesaBufferList = b; return b; } /** * Find an XMesaBuffer by matching X display and colormap but NOT matching * the notThis buffer. */ XMesaBuffer xmesa_find_buffer(XMesaDisplay *dpy, XMesaColormap cmap, XMesaBuffer notThis) { XMesaBuffer b; for (b=XMesaBufferList; b; b=b->Next) { if (b->display==dpy && b->cmap==cmap && b!=notThis) { return b; } } return NULL; } /** * Remove buffer from linked list, delete if no longer referenced. */ static void xmesa_free_buffer(XMesaBuffer buffer) { XMesaBuffer prev = NULL, b; for (b = XMesaBufferList; b; b = b->Next) { if (b == buffer) { struct gl_framebuffer *fb = &buffer->mesa_buffer; /* unlink buffer from list */ if (prev) prev->Next = buffer->Next; else XMesaBufferList = buffer->Next; /* mark as delete pending */ fb->DeletePending = GL_TRUE; /* Since the X window for the XMesaBuffer is going away, we don't * want to dereference this pointer in the future. */ b->frontxrb->drawable = 0; /* Unreference. If count = zero we'll really delete the buffer */ _mesa_reference_framebuffer(&fb, NULL); return; } /* continue search */ prev = b; } /* buffer not found in XMesaBufferList */ _mesa_problem(NULL,"xmesa_free_buffer() - buffer not found\n"); } /**********************************************************************/ /***** Misc Private Functions *****/ /**********************************************************************/ /** * Setup RGB rendering for a window with a True/DirectColor visual. */ static void setup_truecolor(XMesaVisual v, XMesaBuffer buffer, XMesaColormap cmap) { unsigned long rmask, gmask, bmask; (void) buffer; (void) cmap; /* Compute red multiplier (mask) and bit shift */ v->rshift = 0; rmask = GET_REDMASK(v); while ((rmask & 1)==0) { v->rshift++; rmask = rmask >> 1; } /* Compute green multiplier (mask) and bit shift */ v->gshift = 0; gmask = GET_GREENMASK(v); while ((gmask & 1)==0) { v->gshift++; gmask = gmask >> 1; } /* Compute blue multiplier (mask) and bit shift */ v->bshift = 0; bmask = GET_BLUEMASK(v); while ((bmask & 1)==0) { v->bshift++; bmask = bmask >> 1; } /* * Compute component-to-pixel lookup tables and dithering kernel */ { static GLubyte kernel[16] = { 0*16, 8*16, 2*16, 10*16, 12*16, 4*16, 14*16, 6*16, 3*16, 11*16, 1*16, 9*16, 15*16, 7*16, 13*16, 5*16, }; GLint rBits = _mesa_bitcount(rmask); GLint gBits = _mesa_bitcount(gmask); GLint bBits = _mesa_bitcount(bmask); GLint maxBits; GLuint i; /* convert pixel components in [0,_mask] to RGB values in [0,255] */ for (i=0; i<=rmask; i++) v->PixelToR[i] = (unsigned char) ((i * 255) / rmask); for (i=0; i<=gmask; i++) v->PixelToG[i] = (unsigned char) ((i * 255) / gmask); for (i=0; i<=bmask; i++) v->PixelToB[i] = (unsigned char) ((i * 255) / bmask); /* convert RGB values from [0,255] to pixel components */ for (i=0;i<256;i++) { GLint r = gamma_adjust(v->RedGamma, i, 255); GLint g = gamma_adjust(v->GreenGamma, i, 255); GLint b = gamma_adjust(v->BlueGamma, i, 255); v->RtoPixel[i] = (r >> (8-rBits)) << v->rshift; v->GtoPixel[i] = (g >> (8-gBits)) << v->gshift; v->BtoPixel[i] = (b >> (8-bBits)) << v->bshift; } /* overflow protection */ for (i=256;i<512;i++) { v->RtoPixel[i] = v->RtoPixel[255]; v->GtoPixel[i] = v->GtoPixel[255]; v->BtoPixel[i] = v->BtoPixel[255]; } /* setup dithering kernel */ maxBits = rBits; if (gBits > maxBits) maxBits = gBits; if (bBits > maxBits) maxBits = bBits; for (i=0;i<16;i++) { v->Kernel[i] = kernel[i] >> maxBits; } v->undithered_pf = PF_Truecolor; v->dithered_pf = (GET_VISUAL_DEPTH(v)<24) ? PF_Dither_True : PF_Truecolor; } /* * Now check for TrueColor visuals which we can optimize. */ if ( GET_REDMASK(v) ==0x0000ff && GET_GREENMASK(v)==0x00ff00 && GET_BLUEMASK(v) ==0xff0000 && CHECK_BYTE_ORDER(v) && v->BitsPerPixel==32 && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) { /* common 32 bpp config used on SGI, Sun */ v->undithered_pf = v->dithered_pf = PF_8A8B8G8R; /* ABGR */ } else if (GET_REDMASK(v) == 0xff0000 && GET_GREENMASK(v)== 0x00ff00 && GET_BLUEMASK(v) == 0x0000ff && CHECK_BYTE_ORDER(v) && v->RedGamma == 1.0 && v->GreenGamma == 1.0 && v->BlueGamma == 1.0){ if (v->BitsPerPixel==32) { /* if 32 bpp, and visual indicates 8 bpp alpha channel */ if (GET_VISUAL_DEPTH(v) == 32 && v->mesa_visual.alphaBits == 8) v->undithered_pf = v->dithered_pf = PF_8A8R8G8B; /* ARGB */ else v->undithered_pf = v->dithered_pf = PF_8R8G8B; /* xRGB */ } else if (v->BitsPerPixel == 24) { v->undithered_pf = v->dithered_pf = PF_8R8G8B24; /* RGB */ } } else if (GET_REDMASK(v) ==0xf800 && GET_GREENMASK(v)==0x07e0 && GET_BLUEMASK(v) ==0x001f && CHECK_BYTE_ORDER(v) && v->BitsPerPixel==16 && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) { /* 5-6-5 RGB */ v->undithered_pf = PF_5R6G5B; v->dithered_pf = PF_Dither_5R6G5B; } } /** * When a context is bound for the first time, we can finally finish * initializing the context's visual and buffer information. * \param v the XMesaVisual to initialize * \param b the XMesaBuffer to initialize (may be NULL) * \param rgb_flag TRUE = RGBA mode, FALSE = color index mode * \param window the window/pixmap we're rendering into * \param cmap the colormap associated with the window/pixmap * \return GL_TRUE=success, GL_FALSE=failure */ static GLboolean initialize_visual_and_buffer(XMesaVisual v, XMesaBuffer b, XMesaDrawable window, XMesaColormap cmap) { const int xclass = v->visualType; assert(!b || b->xm_visual == v); /* Save true bits/pixel */ v->BitsPerPixel = bits_per_pixel(v); assert(v->BitsPerPixel > 0); /* RGB WINDOW: * We support RGB rendering into almost any kind of visual. */ if (xclass == GLX_TRUE_COLOR || xclass == GLX_DIRECT_COLOR) { setup_truecolor( v, b, cmap ); } else { _mesa_warning(NULL, "XMesa: RGB mode rendering not supported in given visual.\n"); return GL_FALSE; } v->mesa_visual.indexBits = 0; if (getenv("MESA_NO_DITHER")) { v->dithered_pf = v->undithered_pf; } /* * If MESA_INFO env var is set print out some debugging info * which can help Brian figure out what's going on when a user * reports bugs. */ if (getenv("MESA_INFO")) { printf("X/Mesa visual = %p\n", (void *) v); printf("X/Mesa dithered pf = %u\n", v->dithered_pf); printf("X/Mesa undithered pf = %u\n", v->undithered_pf); printf("X/Mesa level = %d\n", v->mesa_visual.level); printf("X/Mesa depth = %d\n", GET_VISUAL_DEPTH(v)); printf("X/Mesa bits per pixel = %d\n", v->BitsPerPixel); } if (b && window) { /* Do window-specific initializations */ /* these should have been set in create_xmesa_buffer */ assert(b->frontxrb->drawable == window); assert(b->frontxrb->pixmap == (XMesaPixmap) window); /* Setup for single/double buffering */ if (v->mesa_visual.doubleBufferMode) { /* Double buffered */ b->shm = check_for_xshm( v->display ); } /* X11 graphics contexts */ b->gc = XCreateGC( v->display, window, 0, NULL ); XMesaSetFunction( v->display, b->gc, GXcopy ); /* cleargc - for glClear() */ b->cleargc = XCreateGC( v->display, window, 0, NULL ); XMesaSetFunction( v->display, b->cleargc, GXcopy ); /* * Don't generate Graphics Expose/NoExpose events in swapbuffers(). * Patch contributed by Michael Pichler May 15, 1995. */ { XGCValues gcvalues; gcvalues.graphics_exposures = False; b->swapgc = XCreateGC(v->display, window, GCGraphicsExposures, &gcvalues); } XMesaSetFunction( v->display, b->swapgc, GXcopy ); } return GL_TRUE; } /* * Convert an RGBA color to a pixel value. */ unsigned long xmesa_color_to_pixel(struct gl_context *ctx, GLubyte r, GLubyte g, GLubyte b, GLubyte a, GLuint pixelFormat) { XMesaContext xmesa = XMESA_CONTEXT(ctx); switch (pixelFormat) { case PF_Truecolor: { unsigned long p; PACK_TRUECOLOR( p, r, g, b ); return p; } case PF_8A8B8G8R: return PACK_8A8B8G8R( r, g, b, a ); case PF_8A8R8G8B: return PACK_8A8R8G8B( r, g, b, a ); case PF_8R8G8B: /* fall through */ case PF_8R8G8B24: return PACK_8R8G8B( r, g, b ); case PF_5R6G5B: return PACK_5R6G5B( r, g, b ); case PF_Dither_True: /* fall through */ case PF_Dither_5R6G5B: { unsigned long p; PACK_TRUEDITHER(p, 1, 0, r, g, b); return p; } default: _mesa_problem(ctx, "Bad pixel format in xmesa_color_to_pixel"); } return 0; } #define NUM_VISUAL_TYPES 6 /** * Convert an X visual type to a GLX visual type. * * \param visualType X visual type (i.e., \c TrueColor, \c StaticGray, etc.) * to be converted. * \return If \c visualType is a valid X visual type, a GLX visual type will * be returned. Otherwise \c GLX_NONE will be returned. * * \note * This code was lifted directly from lib/GL/glx/glcontextmodes.c in the * DRI CVS tree. */ static GLint xmesa_convert_from_x_visual_type( int visualType ) { static const int glx_visual_types[ NUM_VISUAL_TYPES ] = { GLX_STATIC_GRAY, GLX_GRAY_SCALE, GLX_STATIC_COLOR, GLX_PSEUDO_COLOR, GLX_TRUE_COLOR, GLX_DIRECT_COLOR }; return ( (unsigned) visualType < NUM_VISUAL_TYPES ) ? glx_visual_types[ visualType ] : GLX_NONE; } /**********************************************************************/ /***** Public Functions *****/ /**********************************************************************/ /* * Create a new X/Mesa visual. * Input: display - X11 display * visinfo - an XVisualInfo pointer * rgb_flag - GL_TRUE = RGB mode, * GL_FALSE = color index mode * alpha_flag - alpha buffer requested? * db_flag - GL_TRUE = double-buffered, * GL_FALSE = single buffered * stereo_flag - stereo visual? * ximage_flag - GL_TRUE = use an XImage for back buffer, * GL_FALSE = use an off-screen pixmap for back buffer * depth_size - requested bits/depth values, or zero * stencil_size - requested bits/stencil values, or zero * accum_red_size - requested bits/red accum values, or zero * accum_green_size - requested bits/green accum values, or zero * accum_blue_size - requested bits/blue accum values, or zero * accum_alpha_size - requested bits/alpha accum values, or zero * num_samples - number of samples/pixel if multisampling, or zero * level - visual level, usually 0 * visualCaveat - ala the GLX extension, usually GLX_NONE * Return; a new XMesaVisual or 0 if error. */ PUBLIC XMesaVisual XMesaCreateVisual( XMesaDisplay *display, XMesaVisualInfo visinfo, GLboolean rgb_flag, GLboolean alpha_flag, GLboolean db_flag, GLboolean stereo_flag, GLboolean ximage_flag, GLint depth_size, GLint stencil_size, GLint accum_red_size, GLint accum_green_size, GLint accum_blue_size, GLint accum_alpha_size, GLint num_samples, GLint level, GLint visualCaveat ) { char *gamma; XMesaVisual v; GLint red_bits, green_bits, blue_bits, alpha_bits; /* For debugging only */ if (getenv("MESA_XSYNC")) { /* This makes debugging X easier. * In your debugger, set a breakpoint on _XError to stop when an * X protocol error is generated. */ XSynchronize( display, 1 ); } /* Color-index rendering not supported. */ if (!rgb_flag) return NULL; v = (XMesaVisual) CALLOC_STRUCT(xmesa_visual); if (!v) { return NULL; } v->display = display; /* Save a copy of the XVisualInfo struct because the user may Xfree() * the struct but we may need some of the information contained in it * at a later time. */ v->visinfo = malloc(sizeof(*visinfo)); if(!v->visinfo) { free(v); return NULL; } memcpy(v->visinfo, visinfo, sizeof(*visinfo)); /* check for MESA_GAMMA environment variable */ gamma = getenv("MESA_GAMMA"); if (gamma) { v->RedGamma = v->GreenGamma = v->BlueGamma = 0.0; sscanf( gamma, "%f %f %f", &v->RedGamma, &v->GreenGamma, &v->BlueGamma ); if (v->RedGamma<=0.0) v->RedGamma = 1.0; if (v->GreenGamma<=0.0) v->GreenGamma = v->RedGamma; if (v->BlueGamma<=0.0) v->BlueGamma = v->RedGamma; } else { v->RedGamma = v->GreenGamma = v->BlueGamma = 1.0; } v->ximage_flag = ximage_flag; v->mesa_visual.redMask = visinfo->red_mask; v->mesa_visual.greenMask = visinfo->green_mask; v->mesa_visual.blueMask = visinfo->blue_mask; v->visualID = visinfo->visualid; v->screen = visinfo->screen; #if !(defined(__cplusplus) || defined(c_plusplus)) v->visualType = xmesa_convert_from_x_visual_type(visinfo->class); #else v->visualType = xmesa_convert_from_x_visual_type(visinfo->c_class); #endif v->mesa_visual.visualRating = visualCaveat; if (alpha_flag) v->mesa_visual.alphaBits = 8; (void) initialize_visual_and_buffer( v, NULL, 0, 0 ); { const int xclass = v->visualType; if (xclass == GLX_TRUE_COLOR || xclass == GLX_DIRECT_COLOR) { red_bits = _mesa_bitcount(GET_REDMASK(v)); green_bits = _mesa_bitcount(GET_GREENMASK(v)); blue_bits = _mesa_bitcount(GET_BLUEMASK(v)); } else { /* this is an approximation */ int depth; depth = GET_VISUAL_DEPTH(v); red_bits = depth / 3; depth -= red_bits; green_bits = depth / 2; depth -= green_bits; blue_bits = depth; alpha_bits = 0; assert( red_bits + green_bits + blue_bits == GET_VISUAL_DEPTH(v) ); } alpha_bits = v->mesa_visual.alphaBits; } if (!_mesa_initialize_visual(&v->mesa_visual, db_flag, stereo_flag, red_bits, green_bits, blue_bits, alpha_bits, depth_size, stencil_size, accum_red_size, accum_green_size, accum_blue_size, accum_alpha_size, 0)) { free(v); return NULL; } /* XXX minor hack */ v->mesa_visual.level = level; return v; } PUBLIC void XMesaDestroyVisual( XMesaVisual v ) { free(v->visinfo); free(v); } /** * Create a new XMesaContext. * \param v the XMesaVisual * \param share_list another XMesaContext with which to share display * lists or NULL if no sharing is wanted. * \return an XMesaContext or NULL if error. */ PUBLIC XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list ) { static GLboolean firstTime = GL_TRUE; XMesaContext c; struct gl_context *mesaCtx; struct dd_function_table functions; TNLcontext *tnl; if (firstTime) { mtx_init(&_xmesa_lock, mtx_plain); firstTime = GL_FALSE; } /* Note: the XMesaContext contains a Mesa struct gl_context struct (inheritance) */ c = (XMesaContext) CALLOC_STRUCT(xmesa_context); if (!c) return NULL; mesaCtx = &(c->mesa); /* initialize with default driver functions, then plug in XMesa funcs */ _mesa_init_driver_functions(&functions); xmesa_init_driver_functions(v, &functions); if (!_mesa_initialize_context(mesaCtx, API_OPENGL_COMPAT, &v->mesa_visual, share_list ? &(share_list->mesa) : (struct gl_context *) NULL, &functions)) { free(c); return NULL; } /* Enable this to exercise fixed function -> shader translation * with software rendering. */ if (0) { mesaCtx->VertexProgram._MaintainTnlProgram = GL_TRUE; mesaCtx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE; } _mesa_enable_sw_extensions(mesaCtx); #if ENABLE_EXT_timer_query mesaCtx->Extensions.EXT_timer_query = GL_TRUE; #endif /* finish up xmesa context initializations */ c->direct = GL_TRUE; c->swapbytes = CHECK_BYTE_ORDER(v) ? GL_FALSE : GL_TRUE; c->xm_visual = v; c->xm_buffer = NULL; /* set later by XMesaMakeCurrent */ c->display = v->display; c->pixelformat = v->dithered_pf; /* Dithering is enabled by default */ /* Initialize the software rasterizer and helper modules. */ if (!_swrast_CreateContext( mesaCtx ) || !_vbo_CreateContext( mesaCtx ) || !_tnl_CreateContext( mesaCtx ) || !_swsetup_CreateContext( mesaCtx )) { _mesa_free_context_data(&c->mesa); free(c); return NULL; } /* tnl setup */ tnl = TNL_CONTEXT(mesaCtx); tnl->Driver.RunPipeline = _tnl_run_pipeline; /* swrast setup */ xmesa_register_swrast_functions( mesaCtx ); _swsetup_Wakeup(mesaCtx); _mesa_meta_init(mesaCtx); _mesa_compute_version(mesaCtx); /* Exec table initialization requires the version to be computed */ _mesa_initialize_dispatch_tables(mesaCtx); _mesa_initialize_vbo_vtxfmt(mesaCtx); return c; } PUBLIC void XMesaDestroyContext( XMesaContext c ) { struct gl_context *mesaCtx = &c->mesa; _mesa_meta_free( mesaCtx ); _swsetup_DestroyContext( mesaCtx ); _swrast_DestroyContext( mesaCtx ); _tnl_DestroyContext( mesaCtx ); _vbo_DestroyContext( mesaCtx ); _mesa_free_context_data( mesaCtx ); free( c ); } /** * Private function for creating an XMesaBuffer which corresponds to an * X window or pixmap. * \param v the window's XMesaVisual * \param w the window we're wrapping * \return new XMesaBuffer or NULL if error */ PUBLIC XMesaBuffer XMesaCreateWindowBuffer(XMesaVisual v, XMesaWindow w) { XWindowAttributes attr; XMesaBuffer b; XMesaColormap cmap; int depth; assert(v); assert(w); /* Check that window depth matches visual depth */ XGetWindowAttributes( v->display, w, &attr ); depth = attr.depth; if (GET_VISUAL_DEPTH(v) != depth) { _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual (%d) and window (%d)!\n", GET_VISUAL_DEPTH(v), depth); return NULL; } /* Find colormap */ if (attr.colormap) { cmap = attr.colormap; } else { _mesa_warning(NULL, "Window %u has no colormap!\n", (unsigned int) w); /* this is weird, a window w/out a colormap!? */ /* OK, let's just allocate a new one and hope for the best */ cmap = XCreateColormap(v->display, w, attr.visual, AllocNone); } b = create_xmesa_buffer((XMesaDrawable) w, WINDOW, v, cmap); if (!b) return NULL; if (!initialize_visual_and_buffer( v, b, (XMesaDrawable) w, cmap )) { xmesa_free_buffer(b); return NULL; } return b; } /** * Create a new XMesaBuffer from an X pixmap. * * \param v the XMesaVisual * \param p the pixmap * \param cmap the colormap, may be 0 if using a \c GLX_TRUE_COLOR or * \c GLX_DIRECT_COLOR visual for the pixmap * \returns new XMesaBuffer or NULL if error */ PUBLIC XMesaBuffer XMesaCreatePixmapBuffer(XMesaVisual v, XMesaPixmap p, XMesaColormap cmap) { XMesaBuffer b; assert(v); b = create_xmesa_buffer((XMesaDrawable) p, PIXMAP, v, cmap); if (!b) return NULL; if (!initialize_visual_and_buffer(v, b, (XMesaDrawable) p, cmap)) { xmesa_free_buffer(b); return NULL; } return b; } /** * For GLX_EXT_texture_from_pixmap */ XMesaBuffer XMesaCreatePixmapTextureBuffer(XMesaVisual v, XMesaPixmap p, XMesaColormap cmap, int format, int target, int mipmap) { GET_CURRENT_CONTEXT(ctx); XMesaBuffer b; GLuint width, height; assert(v); b = create_xmesa_buffer((XMesaDrawable) p, PIXMAP, v, cmap); if (!b) return NULL; /* get pixmap size, update framebuffer/renderbuffer dims */ xmesa_get_window_size(v->display, b, &width, &height); _mesa_resize_framebuffer(NULL, &(b->mesa_buffer), width, height); if (target == 0) { /* examine dims */ if (ctx->Extensions.ARB_texture_non_power_of_two) { target = GLX_TEXTURE_2D_EXT; } else if ( _mesa_bitcount(width) == 1 && _mesa_bitcount(height) == 1) { /* power of two size */ if (height == 1) { target = GLX_TEXTURE_1D_EXT; } else { target = GLX_TEXTURE_2D_EXT; } } else if (ctx->Extensions.NV_texture_rectangle) { target = GLX_TEXTURE_RECTANGLE_EXT; } else { /* non power of two textures not supported */ XMesaDestroyBuffer(b); return 0; } } b->TextureTarget = target; b->TextureFormat = format; b->TextureMipmap = mipmap; if (!initialize_visual_and_buffer(v, b, (XMesaDrawable) p, cmap)) { xmesa_free_buffer(b); return NULL; } return b; } XMesaBuffer XMesaCreatePBuffer(XMesaVisual v, XMesaColormap cmap, unsigned int width, unsigned int height) { XMesaWindow root; XMesaDrawable drawable; /* X Pixmap Drawable */ XMesaBuffer b; /* allocate pixmap for front buffer */ root = RootWindow( v->display, v->visinfo->screen ); drawable = XCreatePixmap(v->display, root, width, height, v->visinfo->depth); if (!drawable) return NULL; b = create_xmesa_buffer(drawable, PBUFFER, v, cmap); if (!b) return NULL; if (!initialize_visual_and_buffer(v, b, drawable, cmap)) { xmesa_free_buffer(b); return NULL; } return b; } /* * Deallocate an XMesaBuffer structure and all related info. */ PUBLIC void XMesaDestroyBuffer(XMesaBuffer b) { xmesa_free_buffer(b); } /** * Query the current window size and update the corresponding struct gl_framebuffer * and all attached renderbuffers. * Called when: * 1. the first time a buffer is bound to a context. * 2. from glViewport to poll for window size changes * 3. from the XMesaResizeBuffers() API function. * Note: it's possible (and legal) for xmctx to be NULL. That can happen * when resizing a buffer when no rendering context is bound. */ void xmesa_check_and_update_buffer_size(XMesaContext xmctx, XMesaBuffer drawBuffer) { GLuint width, height; xmesa_get_window_size(drawBuffer->display, drawBuffer, &width, &height); if (drawBuffer->mesa_buffer.Width != width || drawBuffer->mesa_buffer.Height != height) { struct gl_context *ctx = xmctx ? &xmctx->mesa : NULL; _mesa_resize_framebuffer(ctx, &(drawBuffer->mesa_buffer), width, height); } } /* * Bind buffer b to context c and make c the current rendering context. */ GLboolean XMesaMakeCurrent( XMesaContext c, XMesaBuffer b ) { return XMesaMakeCurrent2( c, b, b ); } /* * Bind buffer b to context c and make c the current rendering context. */ PUBLIC GLboolean XMesaMakeCurrent2( XMesaContext c, XMesaBuffer drawBuffer, XMesaBuffer readBuffer ) { if (c) { if (!drawBuffer || !readBuffer) return GL_FALSE; /* must specify buffers! */ if (&(c->mesa) == _mesa_get_current_context() && c->mesa.DrawBuffer == &drawBuffer->mesa_buffer && c->mesa.ReadBuffer == &readBuffer->mesa_buffer && XMESA_BUFFER(c->mesa.DrawBuffer)->wasCurrent) { /* same context and buffer, do nothing */ return GL_TRUE; } c->xm_buffer = drawBuffer; /* Call this periodically to detect when the user has begun using * GL rendering from multiple threads. */ _glapi_check_multithread(); xmesa_check_and_update_buffer_size(c, drawBuffer); if (readBuffer != drawBuffer) xmesa_check_and_update_buffer_size(c, readBuffer); _mesa_make_current(&(c->mesa), &drawBuffer->mesa_buffer, &readBuffer->mesa_buffer); /* * Must recompute and set these pixel values because colormap * can be different for different windows. */ c->clearpixel = xmesa_color_to_pixel( &c->mesa, c->clearcolor[0], c->clearcolor[1], c->clearcolor[2], c->clearcolor[3], c->xm_visual->undithered_pf); XMesaSetForeground(c->display, drawBuffer->cleargc, c->clearpixel); /* Solution to Stephane Rehel's problem with glXReleaseBuffersMESA(): */ drawBuffer->wasCurrent = GL_TRUE; } else { /* Detach */ _mesa_make_current( NULL, NULL, NULL ); } return GL_TRUE; } /* * Unbind the context c from its buffer. */ GLboolean XMesaUnbindContext( XMesaContext c ) { /* A no-op for XFree86 integration purposes */ return GL_TRUE; } XMesaContext XMesaGetCurrentContext( void ) { GET_CURRENT_CONTEXT(ctx); if (ctx) { XMesaContext xmesa = XMESA_CONTEXT(ctx); return xmesa; } else { return 0; } } XMesaBuffer XMesaGetCurrentBuffer( void ) { GET_CURRENT_CONTEXT(ctx); if (ctx) { XMesaBuffer xmbuf = XMESA_BUFFER(ctx->DrawBuffer); return xmbuf; } else { return 0; } } /* New in Mesa 3.1 */ XMesaBuffer XMesaGetCurrentReadBuffer( void ) { GET_CURRENT_CONTEXT(ctx); if (ctx) { return XMESA_BUFFER(ctx->ReadBuffer); } else { return 0; } } GLboolean XMesaSetFXmode( GLint mode ) { (void) mode; return GL_FALSE; } /* * Copy the back buffer to the front buffer. If there's no back buffer * this is a no-op. */ PUBLIC void XMesaSwapBuffers( XMesaBuffer b ) { GET_CURRENT_CONTEXT(ctx); if (!b->backxrb) { /* single buffered */ return; } /* If we're swapping the buffer associated with the current context * we have to flush any pending rendering commands first. */ if (ctx && ctx->DrawBuffer == &(b->mesa_buffer)) _mesa_notifySwapBuffers(ctx); if (b->db_mode) { if (b->backxrb->ximage) { /* Copy Ximage (back buf) from client memory to server window */ #if defined(USE_XSHM) if (b->shm) { /*mtx_lock(&_xmesa_lock);*/ XShmPutImage( b->xm_visual->display, b->frontxrb->drawable, b->swapgc, b->backxrb->ximage, 0, 0, 0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height, False ); /*mtx_unlock(&_xmesa_lock);*/ } else #endif { /*mtx_lock(&_xmesa_lock);*/ XMesaPutImage( b->xm_visual->display, b->frontxrb->drawable, b->swapgc, b->backxrb->ximage, 0, 0, 0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height ); /*mtx_unlock(&_xmesa_lock);*/ } } else if (b->backxrb->pixmap) { /* Copy pixmap (back buf) to window (front buf) on server */ /*mtx_lock(&_xmesa_lock);*/ XMesaCopyArea( b->xm_visual->display, b->backxrb->pixmap, /* source drawable */ b->frontxrb->drawable, /* dest. drawable */ b->swapgc, 0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height, 0, 0 /* dest region */ ); /*mtx_unlock(&_xmesa_lock);*/ } } XSync( b->xm_visual->display, False ); } /* * Copy sub-region of back buffer to front buffer */ void XMesaCopySubBuffer( XMesaBuffer b, int x, int y, int width, int height ) { GET_CURRENT_CONTEXT(ctx); /* If we're swapping the buffer associated with the current context * we have to flush any pending rendering commands first. */ if (ctx && ctx->DrawBuffer == &(b->mesa_buffer)) _mesa_notifySwapBuffers(ctx); if (!b->backxrb) { /* single buffered */ return; } if (b->db_mode) { int yTop = b->mesa_buffer.Height - y - height; if (b->backxrb->ximage) { /* Copy Ximage from host's memory to server's window */ #if defined(USE_XSHM) if (b->shm) { /* XXX assuming width and height aren't too large! */ XShmPutImage( b->xm_visual->display, b->frontxrb->drawable, b->swapgc, b->backxrb->ximage, x, yTop, x, yTop, width, height, False ); /* wait for finished event??? */ } else #endif { /* XXX assuming width and height aren't too large! */ XMesaPutImage( b->xm_visual->display, b->frontxrb->drawable, b->swapgc, b->backxrb->ximage, x, yTop, x, yTop, width, height ); } } else { /* Copy pixmap to window on server */ XMesaCopyArea( b->xm_visual->display, b->backxrb->pixmap, /* source drawable */ b->frontxrb->drawable, /* dest. drawable */ b->swapgc, x, yTop, width, height, /* source region */ x, yTop /* dest region */ ); } } } /* * Return a pointer to the XMesa backbuffer Pixmap or XImage. This function * is a way to get "under the hood" of X/Mesa so one can manipulate the * back buffer directly. * Output: pixmap - pointer to back buffer's Pixmap, or 0 * ximage - pointer to back buffer's XImage, or NULL * Return: GL_TRUE = context is double buffered * GL_FALSE = context is single buffered */ GLboolean XMesaGetBackBuffer( XMesaBuffer b, XMesaPixmap *pixmap, XMesaImage **ximage ) { if (b->db_mode) { if (pixmap) *pixmap = b->backxrb->pixmap; if (ximage) *ximage = b->backxrb->ximage; return GL_TRUE; } else { *pixmap = 0; *ximage = NULL; return GL_FALSE; } } /* * Return the depth buffer associated with an XMesaBuffer. * Input: b - the XMesa buffer handle * Output: width, height - size of buffer in pixels * bytesPerValue - bytes per depth value (2 or 4) * buffer - pointer to depth buffer values * Return: GL_TRUE or GL_FALSE to indicate success or failure. */ GLboolean XMesaGetDepthBuffer( XMesaBuffer b, GLint *width, GLint *height, GLint *bytesPerValue, void **buffer ) { struct gl_renderbuffer *rb = b->mesa_buffer.Attachment[BUFFER_DEPTH].Renderbuffer; struct xmesa_renderbuffer *xrb = xmesa_renderbuffer(rb); if (!xrb || !xrb->Base.Buffer) { *width = 0; *height = 0; *bytesPerValue = 0; *buffer = 0; return GL_FALSE; } else { *width = b->mesa_buffer.Width; *height = b->mesa_buffer.Height; *bytesPerValue = b->mesa_buffer.Visual.depthBits <= 16 ? sizeof(GLushort) : sizeof(GLuint); *buffer = (void *) xrb->Base.Buffer; return GL_TRUE; } } void XMesaFlush( XMesaContext c ) { if (c && c->xm_visual) { XSync( c->xm_visual->display, False ); } } const char *XMesaGetString( XMesaContext c, int name ) { (void) c; if (name==XMESA_VERSION) { return "5.0"; } else if (name==XMESA_EXTENSIONS) { return ""; } else { return NULL; } } XMesaBuffer XMesaFindBuffer( XMesaDisplay *dpy, XMesaDrawable d ) { XMesaBuffer b; for (b=XMesaBufferList; b; b=b->Next) { if (b->frontxrb->drawable == d && b->display == dpy) { return b; } } return NULL; } /** * Free/destroy all XMesaBuffers associated with given display. */ void xmesa_destroy_buffers_on_display(XMesaDisplay *dpy) { XMesaBuffer b, next; for (b = XMesaBufferList; b; b = next) { next = b->Next; if (b->display == dpy) { xmesa_free_buffer(b); } } } /* * Look for XMesaBuffers whose X window has been destroyed. * Deallocate any such XMesaBuffers. */ void XMesaGarbageCollect( XMesaDisplay* dpy ) { XMesaBuffer b, next; for (b=XMesaBufferList; b; b=next) { next = b->Next; if (b->display && b->display == dpy && b->frontxrb->drawable && b->type == WINDOW) { XSync(b->display, False); if (!window_exists( b->display, b->frontxrb->drawable )) { /* found a dead window, free the ancillary info */ XMesaDestroyBuffer( b ); } } } } unsigned long XMesaDitherColor( XMesaContext xmesa, GLint x, GLint y, GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha ) { GLint r = (GLint) (red * 255.0F); GLint g = (GLint) (green * 255.0F); GLint b = (GLint) (blue * 255.0F); GLint a = (GLint) (alpha * 255.0F); switch (xmesa->pixelformat) { case PF_Truecolor: { unsigned long p; PACK_TRUECOLOR( p, r, g, b ); return p; } case PF_8A8B8G8R: return PACK_8A8B8G8R( r, g, b, a ); case PF_8A8R8G8B: return PACK_8A8R8G8B( r, g, b, a ); case PF_8R8G8B: return PACK_8R8G8B( r, g, b ); case PF_5R6G5B: return PACK_5R6G5B( r, g, b ); case PF_Dither_5R6G5B: /* fall through */ case PF_Dither_True: { unsigned long p; PACK_TRUEDITHER(p, x, y, r, g, b); return p; } default: _mesa_problem(NULL, "Bad pixel format in XMesaDitherColor"); } return 0; } /* * This is typically called when the window size changes and we need * to reallocate the buffer's back/depth/stencil/accum buffers. */ PUBLIC void XMesaResizeBuffers( XMesaBuffer b ) { GET_CURRENT_CONTEXT(ctx); XMesaContext xmctx = XMESA_CONTEXT(ctx); if (!xmctx) return; xmesa_check_and_update_buffer_size(xmctx, b); } static GLint xbuffer_to_renderbuffer(int buffer) { assert(MAX_AUX_BUFFERS <= 4); switch (buffer) { case GLX_FRONT_LEFT_EXT: return BUFFER_FRONT_LEFT; case GLX_FRONT_RIGHT_EXT: return BUFFER_FRONT_RIGHT; case GLX_BACK_LEFT_EXT: return BUFFER_BACK_LEFT; case GLX_BACK_RIGHT_EXT: return BUFFER_BACK_RIGHT; case GLX_AUX0_EXT: return BUFFER_AUX0; case GLX_AUX1_EXT: case GLX_AUX2_EXT: case GLX_AUX3_EXT: case GLX_AUX4_EXT: case GLX_AUX5_EXT: case GLX_AUX6_EXT: case GLX_AUX7_EXT: case GLX_AUX8_EXT: case GLX_AUX9_EXT: default: /* BadValue error */ return -1; } } PUBLIC void XMesaBindTexImage(XMesaDisplay *dpy, XMesaBuffer drawable, int buffer, const int *attrib_list) { #if 0 GET_CURRENT_CONTEXT(ctx); const GLuint unit = ctx->Texture.CurrentUnit; struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit]; struct gl_texture_object *texObj; #endif struct gl_renderbuffer *rb; struct xmesa_renderbuffer *xrb; GLint b; XMesaImage *img = NULL; GLboolean freeImg = GL_FALSE; b = xbuffer_to_renderbuffer(buffer); if (b < 0) return; if (drawable->TextureFormat == GLX_TEXTURE_FORMAT_NONE_EXT) return; /* BadMatch error */ rb = drawable->mesa_buffer.Attachment[b].Renderbuffer; if (!rb) { /* invalid buffer */ return; } xrb = xmesa_renderbuffer(rb); #if 0 switch (drawable->TextureTarget) { case GLX_TEXTURE_1D_EXT: texObj = texUnit->CurrentTex[TEXTURE_1D_INDEX]; break; case GLX_TEXTURE_2D_EXT: texObj = texUnit->CurrentTex[TEXTURE_2D_INDEX]; break; case GLX_TEXTURE_RECTANGLE_EXT: texObj = texUnit->CurrentTex[TEXTURE_RECT_INDEX]; break; default: return; /* BadMatch error */ } #endif /* * The following is a quick and simple way to implement * BindTexImage. The better way is to write some new FetchTexel() * functions which would extract texels from XImages. We'd still * need to use GetImage when texturing from a Pixmap (front buffer) * but texturing from a back buffer (XImage) would avoid an image * copy. */ /* get XImage */ if (xrb->pixmap) { img = XMesaGetImage(dpy, xrb->pixmap, 0, 0, rb->Width, rb->Height, ~0L, ZPixmap); freeImg = GL_TRUE; } else if (xrb->ximage) { img = xrb->ximage; } /* store the XImage as a new texture image */ if (img) { GLenum format, type, intFormat; if (img->bits_per_pixel == 32) { format = GL_BGRA; type = GL_UNSIGNED_BYTE; intFormat = GL_RGBA; } else if (img->bits_per_pixel == 24) { format = GL_BGR; type = GL_UNSIGNED_BYTE; intFormat = GL_RGB; } else if (img->bits_per_pixel == 16) { format = GL_BGR; type = GL_UNSIGNED_SHORT_5_6_5; intFormat = GL_RGB; } else { _mesa_problem(NULL, "Unexpected XImage format in XMesaBindTexImage"); return; } if (drawable->TextureFormat == GLX_TEXTURE_FORMAT_RGBA_EXT) { intFormat = GL_RGBA; } else if (drawable->TextureFormat == GLX_TEXTURE_FORMAT_RGB_EXT) { intFormat = GL_RGB; } _mesa_TexImage2D(GL_TEXTURE_2D, 0, intFormat, rb->Width, rb->Height, 0, format, type, img->data); if (freeImg) { XMesaDestroyImage(img); } } } PUBLIC void XMesaReleaseTexImage(XMesaDisplay *dpy, XMesaBuffer drawable, int buffer) { const GLint b = xbuffer_to_renderbuffer(buffer); if (b < 0) return; /* no-op for now */ }