mesa: Use _mesa_detach_renderbuffer when deleting a texture

The functional change is that now invalidate_framebuffer is called if
the texture is actually detached from one of the currently bound FBOs.
Previously this was only done for renderbuffers.

The remaining changes make the texture delete path look more similar to
the renderbuffer delete path.  This includes adding relevant spec
quotations to justify the behavior.

Fixes piglit fbo-incomplete "delete texture of bound FBO" test.

v2: Move 'fb->Attachment[i].Texture == att' check from previous patch to
this patch... where it was intended to be in the first place.  Noticed
by Chad.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Chad Versace <chad.versace@linux.intel.com>
Cc: "9.2" <mesa-stable@lists.freedesktop.org>
(cherry picked from commit ef83bd2b9581c680439a5d22979c2f1b49b2834d)

2 files changed, 48 insertions, 20 deletions

diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
index f5a2851b398..53e2ab7c84b 100644
--- a/src/mesa/main/fbobject.c
+++ b/src/mesa/main/fbobject.c
@@ -1223,10 +1223,8 @@ _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.
+ * Remove the specified renderbuffer or texture from any attachment point in
+ * the framebuffer.
  *
  * \returns
  * \c true if the renderbuffer was detached from an attachment point.  \c
@@ -1241,7 +1239,8 @@ _mesa_detach_renderbuffer(struct gl_context *ctx,
    bool progress = false;
 
    for (i = 0; i < BUFFER_COUNT; i++) {
-      if (fb->Attachment[i].Renderbuffer == att) {
+      if (fb->Attachment[i].Texture == att
+          || fb->Attachment[i].Renderbuffer == att) {
          _mesa_remove_attachment(ctx, &fb->Attachment[i]);
          progress = true;
       }
@@ -1286,6 +1285,23 @@ _mesa_DeleteRenderbuffers(GLsizei n, const GLuint *renderbuffers)
                _mesa_BindRenderbuffer(GL_RENDERBUFFER_EXT, 0);
             }
 
+            /* Section 4.4.2 (Attaching Images to Framebuffer Objects),
+             * subsection "Attaching Renderbuffer Images to a Framebuffer," of
+             * the OpenGL 3.1 spec says:
+             *
+             *     "If a renderbuffer object is deleted while its image is
+             *     attached to one or more attachment points in the currently
+             *     bound framebuffer, then it is as if FramebufferRenderbuffer
+             *     had been called, with a renderbuffer of 0, for each
+             *     attachment point to which this image was attached in the
+             *     currently bound framebuffer. In other words, this
+             *     renderbuffer image is first detached from all attachment
+             *     points in the currently bound framebuffer. Note that the
+             *     renderbuffer image is specifically not detached from any
+             *     non-bound framebuffers. Detaching the image from any
+             *     non-bound framebuffers is the responsibility of the
+             *     application.
+             */
             if (_mesa_is_user_fbo(ctx->DrawBuffer)) {
                _mesa_detach_renderbuffer(ctx, ctx->DrawBuffer, rb);
             }
diff --git a/src/mesa/main/texobj.c b/src/mesa/main/texobj.c
index 334dee77b91..9942fb1b48d 100644
--- a/src/mesa/main/texobj.c
+++ b/src/mesa/main/texobj.c
@@ -1040,23 +1040,35 @@ static void
 unbind_texobj_from_fbo(struct gl_context *ctx,
                        struct gl_texture_object *texObj)
 {
-   const GLuint n = (ctx->DrawBuffer == ctx->ReadBuffer) ? 1 : 2;
-   GLuint i;
+   bool progress = false;
 
-   for (i = 0; i < n; i++) {
-      struct gl_framebuffer *fb = (i == 0) ? ctx->DrawBuffer : ctx->ReadBuffer;
-      if (_mesa_is_user_fbo(fb)) {
-         GLuint j;
-         for (j = 0; j < BUFFER_COUNT; j++) {
-            if (fb->Attachment[j].Type == GL_TEXTURE &&
-                fb->Attachment[j].Texture == texObj) {
-	       /* Vertices are already flushed by _mesa_DeleteTextures */
-	       ctx->NewState |= _NEW_BUFFERS;
-               _mesa_remove_attachment(ctx, fb->Attachment + j);         
-            }
-         }
-      }
+   /* Section 4.4.2 (Attaching Images to Framebuffer Objects), subsection
+    * "Attaching Texture Images to a Framebuffer," of the OpenGL 3.1 spec
+    * says:
+    *
+    *     "If a texture object is deleted while its image is attached to one
+    *     or more attachment points in the currently bound framebuffer, then
+    *     it is as if FramebufferTexture* had been called, with a texture of
+    *     zero, for each attachment point to which this image was attached in
+    *     the currently bound framebuffer. In other words, this texture image
+    *     is first detached from all attachment points in the currently bound
+    *     framebuffer. Note that the texture image is specifically not
+    *     detached from any other framebuffer objects. Detaching the texture
+    *     image from any other framebuffer objects is the responsibility of
+    *     the application."
+    */
+   if (_mesa_is_user_fbo(ctx->DrawBuffer)) {
+      progress = _mesa_detach_renderbuffer(ctx, ctx->DrawBuffer, texObj);
    }
+   if (_mesa_is_user_fbo(ctx->ReadBuffer)
+       && ctx->ReadBuffer != ctx->DrawBuffer) {
+      progress = _mesa_detach_renderbuffer(ctx, ctx->ReadBuffer, texObj)
+         || progress;
+   }
+
+   if (progress)
+      /* Vertices are already flushed by _mesa_DeleteTextures */
+      ctx->NewState |= _NEW_BUFFERS;
 }