Mesa (arb_fbo): mesa: fix some renderbuffer/framebuffer delete semantics

[Brian Paul]

Module: Mesa
Branch: arb_fbo
Commit: aafcd8d8679641e5c86e4479b79bc41b9f6002eb
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=aafcd8d8679641e5c86e4479b79bc41b9f6002eb

Author: Brian Paul <brianp at vmware.com>
Date:   Wed Jan 21 11:17:45 2009 -0700

mesa: fix some renderbuffer/framebuffer delete semantics

Need to unbind buffers if referenced by the current read/draw pointers when
being deleted.

---

 src/mesa/main/fbobject.c |   34 +++++++++++++++++++++++++++++++++-
 1 files changed, 33 insertions(+), 1 deletions(-)

diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
index 73f891d..85e15a6 100644
--- a/src/mesa/main/fbobject.c
+++ b/src/mesa/main/fbobject.c
@@ -683,6 +683,26 @@ _mesa_BindRenderbufferEXT(GLenum target, GLuint renderbuffer)
 }
 
 
+/**
+ * If the given renderbuffer is anywhere attached to the framebuffer, detach
+ * the renderbuffer.
+ * This is used when a renderbuffer object is deleted.
+ * The spec calls for unbinding.
+ */
+static void
+detach_renderbuffer(GLcontext *ctx,
+                    struct gl_framebuffer *fb,
+                    struct gl_renderbuffer *rb)
+{
+   GLuint i;
+   for (i = 0; i < BUFFER_COUNT; i++) {
+      if (fb->Attachment[i].Renderbuffer == rb) {
+         _mesa_remove_attachment(ctx, &fb->Attachment[i]);
+      }
+   }
+}
+
+
 void GLAPIENTRY
 _mesa_DeleteRenderbuffersEXT(GLsizei n, const GLuint *renderbuffers)
 {
@@ -704,6 +724,13 @@ _mesa_DeleteRenderbuffersEXT(GLsizei n, const GLuint *renderbuffers)
                _mesa_BindRenderbufferEXT(GL_RENDERBUFFER_EXT, 0);
             }
 
+            if (ctx->DrawBuffer->Name) {
+               detach_renderbuffer(ctx, ctx->DrawBuffer, rb);
+            }
+            if (ctx->ReadBuffer->Name && ctx->ReadBuffer != ctx->DrawBuffer) {
+               detach_renderbuffer(ctx, ctx->ReadBuffer, rb);
+            }
+
 	    /* Remove from hash table immediately, to free the ID.
              * But the object will not be freed until it's no longer
              * referenced anywhere else.
@@ -1201,7 +1228,12 @@ _mesa_DeleteFramebuffersEXT(GLsizei n, const GLuint *framebuffers)
             if (fb == ctx->DrawBuffer) {
                /* bind default */
                ASSERT(fb->RefCount >= 2);
-               _mesa_BindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+               _mesa_BindFramebufferEXT(GL_DRAW_FRAMEBUFFER_EXT, 0);
+            }
+            if (fb == ctx->ReadBuffer) {
+               /* bind default */
+               ASSERT(fb->RefCount >= 2);
+               _mesa_BindFramebufferEXT(GL_READ_FRAMEBUFFER_EXT, 0);
             }
 
 	    /* remove from hash table immediately, to free the ID */