[Mesa-dev] [RFC PATCH 16/26] mesa: support multisample textures in framebuffer completeness check

[Chris Forbes]

- sample count must be the same on all attachments
- fixedsamplepositions must be the same on all attachments
(renderbuffers have fixedsamplepositions=true implicitly; only
multisample textures can choose to have it false)

Signed-off-by: Chris Forbes <chrisf at ijw.co.nz>
---
 src/mesa/main/fbobject.c | 35 ++++++++++++++++++++++++++---------
 1 file changed, 26 insertions(+), 9 deletions(-)

diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
index c541695..b1d2eb4 100644
--- a/src/mesa/main/fbobject.c
+++ b/src/mesa/main/fbobject.c
@@ -681,6 +681,7 @@ _mesa_test_framebuffer_completeness(struct gl_context *ctx,
    GLenum intFormat = GL_NONE; /* color buffers' internal format */
    GLuint minWidth = ~0, minHeight = ~0, maxWidth = 0, maxHeight = 0;
    GLint numSamples = -1;
+   GLint fixedSampleLocations = -1;
    GLint i;
    GLuint j;
 
@@ -756,6 +757,12 @@ _mesa_test_framebuffer_completeness(struct gl_context *ctx,
             fbo_incomplete("texture attachment incomplete", -1);
             return;
          }
+
+         if (numSamples < 0)
+            numSamples = att->Texture->NumSamples;
+
+         if (fixedSampleLocations < 0)
+            fixedSampleLocations = att->Texture->FixedSampleLocations;
       }
       else if (att->Type == GL_RENDERBUFFER_EXT) {
          minWidth = MIN2(minWidth, att->Renderbuffer->Width);
@@ -765,21 +772,23 @@ _mesa_test_framebuffer_completeness(struct gl_context *ctx,
          f = att->Renderbuffer->InternalFormat;
          attFormat = att->Renderbuffer->Format;
          numImages++;
+
+         if (numSamples < 0)
+            numSamples = att->Renderbuffer->NumSamples;
+
+         /* RENDERBUFFER has fixedSampleLocations implicitly true */
+         if (fixedSampleLocations < 0)
+            fixedSampleLocations = GL_TRUE;
       }
       else {
          assert(att->Type == GL_NONE);
          continue;
       }
 
-      if (att->Renderbuffer && numSamples < 0) {
-         /* first buffer */
-         numSamples = att->Renderbuffer->NumSamples;
-      }
-
       /* check if integer color */
       fb->_IntegerColor = _mesa_is_format_integer_color(attFormat);
 
-      /* Error-check width, height, format, samples
+      /* Error-check width, height, format, samples, fixedSampleLocations
        */
       if (numImages == 1) {
          /* save format, num samples */
@@ -802,10 +811,18 @@ _mesa_test_framebuffer_completeness(struct gl_context *ctx,
                return;
             }
          }
-         if (att->Renderbuffer &&
-             att->Renderbuffer->NumSamples != numSamples) {
+
+         if ((att->Type == GL_RENDERBUFFER && att->Renderbuffer->NumSamples != numSamples) ||
+             (att->Type == GL_TEXTURE && att->Texture->NumSamples != numSamples)) {
+            fb->_Status = GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE;
+            fbo_incomplete("inconsistent number of samples", i);
+            return;
+         }
+
+         if ((att->Type == GL_RENDERBUFFER && GL_TRUE != fixedSampleLocations) ||
+             (att->Type == GL_TEXTURE && att->Texture->FixedSampleLocations != fixedSampleLocations)) {
             fb->_Status = GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE;
-            fbo_incomplete("inconsistant number of samples", i);
+            fbo_incomplete("inconsistent fixedsamplelocations", i);
             return;
          }
       }
-- 
1.8.0.3