initial support for GL_EXT_framebuffer_object

src/mesa/main/buffers.c

@@ -35,6 +35,7 @@
 #include "context.h"
 #include "depth.h"
 #include "enums.h"
+#include "fbobject.h"
 #include "stencil.h"
 #include "state.h"
 #include "mtypes.h"
@@ -294,16 +295,34 @@ read_buffer_enum_to_bitmask(GLenum buffer)
 void GLAPIENTRY
 _mesa_DrawBuffer( GLenum mode )
 {
-   GLenum destMask, supportedMask;
    GET_CURRENT_CONTEXT(ctx);
    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* too complex... */
 
    if (MESA_VERBOSE & VERBOSE_API)
       _mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(mode));
 
-   /*
+   if (ctx->Extensions.EXT_framebuffer_object && ctx->CurrentFramebuffer) {
-    * Do error checking and compute the _DrawDestMask bitfield.
+      /* Set drawbuffer for a framebuffer object */
-    */
+      if (mode == GL_NONE) {
+         ctx->CurrentFramebuffer->DrawBuffer[0] = mode;
+      }
+      else {
+         const GLint k = mode - GL_COLOR_ATTACHMENT0_EXT;
+         if (k >= 0 && k < ctx->Const.MaxColorAttachments) {
+            /* XXX check that the attachment point's Type != GL_NONE */
+            ctx->CurrentFramebuffer->DrawBuffer[0] = mode;
+         }
+         else {
+            _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(mode)");
+            return;
+         }
+      }
+   }
+   else {
+      /* conventional behaviour */
+      /* Do error checking and compute the _DrawDestMask bitfield. */
+      GLenum destMask, supportedMask;
+
       destMask = draw_buffer_enum_to_bitmask(mode);
       if (destMask == ~0u) {
          _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(mode)");
@@ -321,6 +340,7 @@ _mesa_DrawBuffer( GLenum mode )
       ctx->Color.DrawBuffer[0] = mode;
       ctx->Color._DrawDestMask[0] = destMask;
       ctx->NewState |= _NEW_COLOR;
+   }
 
    /*
     * Call device driver function.
@@ -337,8 +357,6 @@ _mesa_DrawBuffer( GLenum mode )
 void GLAPIENTRY
 _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers)
 {
-   GLint i;
-   GLuint usedBufferMask, supportedMask;
    GET_CURRENT_CONTEXT(ctx);
    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 
@@ -347,6 +365,44 @@ _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers)
       return;
    }
 
+   if (ctx->Extensions.EXT_framebuffer_object && ctx->CurrentFramebuffer) {
+      /* Set drawbuffers for a framebuffer object */
+      GLint i;
+      GLuint usedAttachments = 0x0;
+      for (i = 0; i < n; i++) {
+         if (buffers[i] == GL_NONE) {
+            /* OK */
+            ctx->CurrentFramebuffer->DrawBuffer[i] = GL_NONE;
+         }
+         else {
+            const GLint k = buffers[i] - GL_COLOR_ATTACHMENT0_EXT;
+            if (k >= 0 && k < ctx->Const.MaxColorAttachments) {
+               /* XXX check that the attachment point's Type != GL_NONE */
+               if ((1 << k) & usedAttachments) {
+                  _mesa_error(ctx, GL_INVALID_OPERATION,
+                              "glDrawBuffersARB(duplicated attachment)");
+                  return;
+               }
+               usedAttachments |= (1 << k);
+               ctx->CurrentFramebuffer->DrawBuffer[i] = buffers[i];
+            }
+            else {
+               _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffersARB(mode)");
+               return;
+            }
+         }
+      }
+
+      /* set remaining color outputs to NONE */
+      for (i = n; i < ctx->Const.MaxDrawBuffers; i++) {
+         ctx->CurrentFramebuffer->DrawBuffer[i] = GL_NONE;
+      }
+   }
+   else {
+      /* Conventional operation */
+      GLint i;
+      GLuint usedBufferMask, supportedMask;
+
       supportedMask = supported_buffer_bitmask(ctx);
       usedBufferMask = 0;
       for (i = 0; i < n; i++) {
@@ -362,7 +418,7 @@ _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers)
             return;
          }
          if (destMask & usedBufferMask) {
-         /* can't use a dest buffer more than once! */
+            /* can't specify a dest buffer more than once! */
             _mesa_error(ctx, GL_INVALID_OPERATION,
                         "glDrawBuffersARB(duplicated buffer)");
             return;
@@ -374,7 +430,14 @@ _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers)
          ctx->Color._DrawDestMask[i] = destMask;
       }
 
+      /* set remaining color outputs to NONE */
+      for (i = n; i < ctx->Const.MaxDrawBuffers; i++) {
+         ctx->Color.DrawBuffer[i] = GL_NONE;
+         ctx->Color._DrawDestMask[i] = 0;
+      }
+
       ctx->NewState |= _NEW_COLOR;
+   }
 
    /*
     * Call device driver function.
@@ -398,13 +461,33 @@ _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers)
 void GLAPIENTRY
 _mesa_ReadBuffer( GLenum mode )
 {
-   GLuint srcMask, supportedMask;
    GET_CURRENT_CONTEXT(ctx);
    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 
    if (MESA_VERBOSE & VERBOSE_API)
       _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(mode));
 
+   if (ctx->Extensions.EXT_framebuffer_object && ctx->CurrentFramebuffer) {
+      /* Set readbuffer for a framebuffer object */
+      if (mode == GL_NONE) {
+         ctx->CurrentFramebuffer->ReadBuffer = mode;
+      }
+      else {
+         const GLint k = mode - GL_COLOR_ATTACHMENT0_EXT;
+         if (k >= 0 && k < ctx->Const.MaxColorAttachments) {
+            /* XXX check that the attachment point's Type != GL_NONE */
+            ctx->CurrentFramebuffer->ReadBuffer = mode;
+         }
+         else {
+            _mesa_error(ctx, GL_INVALID_ENUM, "glReadBuffer(mode)");
+            return;
+         }
+      }
+   }
+   else {
+      /* conventional operation */
+      GLuint srcMask, supportedMask;
+
       srcMask = read_buffer_enum_to_bitmask(mode);
       if (srcMask == ~0u) {
          _mesa_error(ctx, GL_INVALID_ENUM, "glReadBuffer(mode)");
@@ -418,6 +501,7 @@ _mesa_ReadBuffer( GLenum mode )
       ctx->Pixel._ReadSrcMask = srcMask;
       ctx->Pixel.ReadBuffer = mode;
       ctx->NewState |= _NEW_PIXEL;
+   }
 
    /*
     * Call device driver function.