xm_dd.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

            /* clear back color buffer */
            struct gl_renderbuffer *backRb
               = ctx->DrawBuffer->Attachment[BUFFER_BACK_LEFT].Renderbuffer;
            if (b->backxrb == xmesa_renderbuffer(backRb)) {
               /* renderbuffer is not wrapped - great! */
               b->backxrb->clearFunc(ctx, b->backxrb, x, y, width, height);
               buffers &= ~BUFFER_BIT_BACK_LEFT;
            }
         }
      }
   }
   if (buffers)
      _swrast_Clear(ctx, buffers);
}


#ifndef XFree86Server
/* XXX these functions haven't been tested in the Xserver environment */


/**
 * Check if we can do an optimized glDrawPixels into an 8R8G8B visual.
 */
static GLboolean
can_do_DrawPixels_8R8G8B(GLcontext *ctx, GLenum format, GLenum type)
{
   if (format == GL_BGRA &&
       type == GL_UNSIGNED_BYTE &&
       ctx->DrawBuffer &&
       ctx->DrawBuffer->Name == 0 &&
       ctx->Pixel.ZoomX == 1.0 &&        /* no zooming */
       ctx->Pixel.ZoomY == 1.0 &&
       ctx->_ImageTransferState == 0 /* no color tables, scale/bias, etc */) {
      const SWcontext *swrast = SWRAST_CONTEXT(ctx);

      if (swrast->NewState)
         _swrast_validate_derived( ctx );
      
      if ((swrast->_RasterMask & ~CLIP_BIT) == 0) /* no blend, z-test, etc */ {
         struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0];
         if (rb) {
            struct xmesa_renderbuffer *xrb = xmesa_renderbuffer(rb->Wrapped);
            if (xrb &&
                xrb->pixmap && /* drawing to pixmap or window */
                xrb->Base.AlphaBits == 0) {
               return GL_TRUE;
            }
         }
      }
   }
   return GL_FALSE;
}


/**
 * This function implements glDrawPixels() with an XPutImage call when
 * drawing to the front buffer (X Window drawable).
 * The image format must be GL_BGRA to match the PF_8R8G8B pixel format.
 */
static void
xmesa_DrawPixels_8R8G8B( GLcontext *ctx,
                         GLint x, GLint y, GLsizei width, GLsizei height,
                         GLenum format, GLenum type,
                         const struct gl_pixelstore_attrib *unpack,
                         const GLvoid *pixels )
{
   if (can_do_DrawPixels_8R8G8B(ctx, format, type)) {
      const SWcontext *swrast = SWRAST_CONTEXT( ctx );
      struct gl_pixelstore_attrib clippedUnpack = *unpack;
      int dstX = x;
      int dstY = y;
      int w = width;
      int h = height;

      if (swrast->NewState)
         _swrast_validate_derived( ctx );

      if (unpack->BufferObj->Name) {
         /* unpack from PBO */
         GLubyte *buf;
         if (!_mesa_validate_pbo_access(2, unpack, width, height, 1,
                                        format, type, pixels)) {
            _mesa_error(ctx, GL_INVALID_OPERATION,
                        "glDrawPixels(invalid PBO access)");
            return;
         }
         buf = (GLubyte *) ctx->Driver.MapBuffer(ctx,
                                                 GL_PIXEL_UNPACK_BUFFER_EXT,
                                                 GL_READ_ONLY_ARB,
                                                 unpack->BufferObj);
         if (!buf) {
            /* buffer is already mapped - that's an error */
            _mesa_error(ctx, GL_INVALID_OPERATION,
                        "glDrawPixels(PBO is mapped)");
            return;
         }
         pixels = ADD_POINTERS(buf, pixels);
      }

      if (_mesa_clip_drawpixels(ctx, &dstX, &dstY, &w, &h, &clippedUnpack)) {
         const XMesaContext xmesa = XMESA_CONTEXT(ctx);
         XMesaDisplay *dpy = xmesa->xm_visual->display;
         XMesaBuffer xmbuf = XMESA_BUFFER(ctx->DrawBuffer);
         const XMesaGC gc = xmbuf->cleargc;  /* effected by glColorMask */
         struct xmesa_renderbuffer *xrb
            = xmesa_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0]->Wrapped);
         const int srcX = clippedUnpack.SkipPixels;
         const int srcY = clippedUnpack.SkipRows;
         const int rowLength = clippedUnpack.RowLength;
         XMesaImage ximage;

         ASSERT(xmesa->xm_visual->dithered_pf == PF_8R8G8B);
         ASSERT(xmesa->xm_visual->undithered_pf == PF_8R8G8B);
         ASSERT(dpy);
         ASSERT(gc);

         /* This is a little tricky since all coordinates up to now have
          * been in the OpenGL bottom-to-top orientation.  X is top-to-bottom
          * so we have to carefully compute the Y coordinates/addresses here.
          */
         MEMSET(&ximage, 0, sizeof(XMesaImage));
         ximage.width = width;
         ximage.height = height;
         ximage.format = ZPixmap;
         ximage.data = (char *) pixels
            + ((srcY + h - 1) * rowLength + srcX) * 4;
         ximage.byte_order = LSBFirst;
         ximage.bitmap_unit = 32;
         ximage.bitmap_bit_order = LSBFirst;
         ximage.bitmap_pad = 32;
         ximage.depth = 32;
         ximage.bits_per_pixel = 32;
         ximage.bytes_per_line = -rowLength * 4; /* negative to flip image */
         /* it seems we don't need to set the ximage.red/green/blue_mask fields */
         /* flip Y axis for dest position */
         dstY = YFLIP(xrb, dstY) - h + 1;
         XPutImage(dpy, xrb->pixmap, gc, &ximage, 0, 0, dstX, dstY, w, h);
      }

      if (unpack->BufferObj->Name) {
         ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
                                 unpack->BufferObj);
      }
   }
   else {
      /* software fallback */
      _swrast_DrawPixels(ctx, x, y, width, height,
                         format, type, unpack, pixels);
   }
}



/**
 * Check if we can do an optimized glDrawPixels into an 5R6G5B visual.
 */
static GLboolean
can_do_DrawPixels_5R6G5B(GLcontext *ctx, GLenum format, GLenum type)
{
   if (format == GL_RGB &&
       type == GL_UNSIGNED_SHORT_5_6_5 &&
       !ctx->Color.DitherFlag &&  /* no dithering */
       ctx->DrawBuffer &&
       ctx->DrawBuffer->Name == 0 &&
       ctx->Pixel.ZoomX == 1.0 &&        /* no zooming */
       ctx->Pixel.ZoomY == 1.0 &&
       ctx->_ImageTransferState == 0 /* no color tables, scale/bias, etc */) {
      const SWcontext *swrast = SWRAST_CONTEXT(ctx);

      if (swrast->NewState)
         _swrast_validate_derived( ctx );
      
      if ((swrast->_RasterMask & ~CLIP_BIT) == 0) /* no blend, z-test, etc */ {
         struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0];
         if (rb) {
            struct xmesa_renderbuffer *xrb = xmesa_renderbuffer(rb->Wrapped);
            if (xrb &&
                xrb->pixmap && /* drawing to pixmap or window */
                xrb->Base.AlphaBits == 0) {
               return GL_TRUE;
            }
         }
      }
   }
   return GL_FALSE;
}


/**
 * This function implements glDrawPixels() with an XPutImage call when
 * drawing to the front buffer (X Window drawable).  The image format
 * must be GL_RGB and image type must be GL_UNSIGNED_SHORT_5_6_5 to
 * match the PF_5R6G5B pixel format.
 */
static void
xmesa_DrawPixels_5R6G5B( GLcontext *ctx,
                         GLint x, GLint y, GLsizei width, GLsizei height,
                         GLenum format, GLenum type,
                         const struct gl_pixelstore_attrib *unpack,
                         const GLvoid *pixels )
{
   if (can_do_DrawPixels_5R6G5B(ctx, format, type)) {
      const SWcontext *swrast = SWRAST_CONTEXT( ctx );
      struct gl_pixelstore_attrib clippedUnpack = *unpack;
      int dstX = x;
      int dstY = y;
      int w = width;
      int h = height;

      if (swrast->NewState)
         _swrast_validate_derived( ctx );
      
      if (unpack->BufferObj->Name) {
         /* unpack from PBO */
         GLubyte *buf;
         if (!_mesa_validate_pbo_access(2, unpack, width, height, 1,
                                        format, type, pixels)) {
            _mesa_error(ctx, GL_INVALID_OPERATION,
                        "glDrawPixels(invalid PBO access)");
            return;
         }
         buf = (GLubyte *) ctx->Driver.MapBuffer(ctx,
                                                 GL_PIXEL_UNPACK_BUFFER_EXT,
                                                 GL_READ_ONLY_ARB,
                                                 unpack->BufferObj);
         if (!buf) {
            /* buffer is already mapped - that's an error */
            _mesa_error(ctx, GL_INVALID_OPERATION,
                        "glDrawPixels(PBO is mapped)");
            return;
         }
         pixels = ADD_POINTERS(buf, pixels);
      }

      if (_mesa_clip_drawpixels(ctx, &dstX, &dstY, &w, &h, &clippedUnpack)) {
         const XMesaContext xmesa = XMESA_CONTEXT(ctx);
         XMesaDisplay *dpy = xmesa->xm_visual->display;
         XMesaBuffer xmbuf = XMESA_BUFFER(ctx->DrawBuffer);
         const XMesaGC gc = xmbuf->cleargc;  /* effected by glColorMask */
         struct xmesa_renderbuffer *xrb
            = xmesa_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0]->Wrapped);
         const int srcX = clippedUnpack.SkipPixels;
         const int srcY = clippedUnpack.SkipRows;
         const int rowLength = clippedUnpack.RowLength;
         XMesaImage ximage;

         ASSERT(xmesa->xm_visual->undithered_pf == PF_5R6G5B);
         ASSERT(dpy);
         ASSERT(gc);

         /* This is a little tricky since all coordinates up to now have
          * been in the OpenGL bottom-to-top orientation.  X is top-to-bottom
          * so we have to carefully compute the Y coordinates/addresses here.
          */
         MEMSET(&ximage, 0, sizeof(XMesaImage));
         ximage.width = width;
         ximage.height = height;
         ximage.format = ZPixmap;
         ximage.data = (char *) pixels
            + ((srcY + h - 1) * rowLength + srcX) * 2;
         ximage.byte_order = LSBFirst;
         ximage.bitmap_unit = 16;
         ximage.bitmap_bit_order = LSBFirst;
         ximage.bitmap_pad = 16;
         ximage.depth = 16;
         ximage.bits_per_pixel = 16;
         ximage.bytes_per_line = -rowLength * 2; /* negative to flip image */
         /* it seems we don't need to set the ximage.red/green/blue_mask fields */
         /* flip Y axis for dest position */
         dstY = YFLIP(xrb, dstY) - h + 1;
         XPutImage(dpy, xrb->pixmap, gc, &ximage, 0, 0, dstX, dstY, w, h);
      }

      if (unpack->BufferObj->Name) {
         ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
                                 unpack->BufferObj);
      }
   }
   else {
      /* software fallback */
      _swrast_DrawPixels(ctx, x, y, width, height,
                         format, type, unpack, pixels);
   }
}


/**
 * Determine if we can do an optimized glCopyPixels.
 */
static GLboolean
can_do_CopyPixels(GLcontext *ctx, GLenum type)
{
   if (type == GL_COLOR &&
       ctx->_ImageTransferState == 0 &&  /* no color tables, scale/bias, etc */
       ctx->Pixel.ZoomX == 1.0 &&        /* no zooming */
       ctx->Pixel.ZoomY == 1.0 &&
       ctx->Color.DrawBuffer[0] == GL_FRONT &&  /* copy to front buf */
       ctx->Pixel.ReadBuffer == GL_FRONT &&    /* copy from front buf */
       ctx->ReadBuffer->_ColorReadBuffer &&
       ctx->DrawBuffer->_ColorDrawBuffers[0]) {
      const SWcontext *swrast = SWRAST_CONTEXT( ctx );

      if (swrast->NewState)
         _swrast_validate_derived( ctx );

      if ((swrast->_RasterMask & ~CLIP_BIT) == 0x0 &&
          ctx->ReadBuffer &&
          ctx->ReadBuffer->_ColorReadBuffer &&
          ctx->DrawBuffer &&
          ctx->DrawBuffer->_ColorDrawBuffers[0]) {
         struct xmesa_renderbuffer *srcXrb
            = xmesa_renderbuffer(ctx->ReadBuffer->_ColorReadBuffer->Wrapped);
         struct xmesa_renderbuffer *dstXrb
            = xmesa_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0]->Wrapped);
         if (srcXrb->pixmap && dstXrb->pixmap) {
            return GL_TRUE;
         }
      }
   }
   return GL_FALSE;
}


/**
 * Implement glCopyPixels for the front color buffer (or back buffer Pixmap)
 * for the color buffer.  Don't support zooming, pixel transfer, etc.
 * We do support copying from one window to another, ala glXMakeCurrentRead.
 */
static void
xmesa_CopyPixels( GLcontext *ctx,
                  GLint srcx, GLint srcy, GLsizei width, GLsizei height,
                  GLint destx, GLint desty, GLenum type )
{
   if (can_do_CopyPixels(ctx, type)) {
      const XMesaContext xmesa = XMESA_CONTEXT(ctx);
      XMesaDisplay *dpy = xmesa->xm_visual->display;
      XMesaBuffer xmbuf = XMESA_BUFFER(ctx->DrawBuffer);
      const XMesaGC gc = xmbuf->cleargc;  /* effected by glColorMask */
      struct xmesa_renderbuffer *srcXrb
         = xmesa_renderbuffer(ctx->ReadBuffer->_ColorReadBuffer->Wrapped);
      struct xmesa_renderbuffer *dstXrb
         = xmesa_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0]->Wrapped);

      ASSERT(dpy);
      ASSERT(gc);

      /* Note: we don't do any special clipping work here.  We could,
       * but X will do it for us.
       */
      srcy = YFLIP(srcXrb, srcy) - height + 1;
      desty = YFLIP(dstXrb, desty) - height + 1;
      XCopyArea(dpy, srcXrb->pixmap, dstXrb->pixmap, gc,
                srcx, srcy, width, height, destx, desty);
   }
   else {
      _swrast_CopyPixels(ctx, srcx, srcy, width, height, destx, desty, type );
   }
}

#endif /* XFree86Server */



/*
 * Every driver should implement a GetString function in order to
 * return a meaningful GL_RENDERER string.
 */
static const GLubyte *
get_string( GLcontext *ctx, GLenum name )
{
   (void) ctx;
   switch (name) {
      case GL_RENDERER:
#ifdef XFree86Server
         return (const GLubyte *) "Mesa GLX Indirect";
#else
         return (const GLubyte *) "Mesa X11";
#endif
      case GL_VENDOR:
#ifdef XFree86Server
         return (const GLubyte *) "Mesa project: www.mesa3d.org";
#else
         return NULL;
#endif
      default:
         return NULL;
   }
}


/*
 * We implement the glEnable function only because we care about
 * dither enable/disable.
 */
static void
enable( GLcontext *ctx, GLenum pname, GLboolean state )
{
   const XMesaContext xmesa = XMESA_CONTEXT(ctx);

   switch (pname) {
      case GL_DITHER:
         if (state)
            xmesa->pixelformat = xmesa->xm_visual->dithered_pf;
         else
            xmesa->pixelformat = xmesa->xm_visual->undithered_pf;