[Mesa-dev] [PATCH 3/4] mesa: add Layered field to framebuffers

[Jordan Justen]

When checking framebuffer completeness, we test each attachment.
We verify that all attachments are consistent in terms of layers.

1. They must all be layered, or all non-layered
2. If they are layered, they must match in depth

Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
---
 src/mesa/main/fbobject.c |   20 ++++++++++++++++++++
 src/mesa/main/mtypes.h   |    2 ++
 2 files changed, 22 insertions(+)

diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
index ce1cb0e..419e871 100644
--- a/src/mesa/main/fbobject.c
+++ b/src/mesa/main/fbobject.c
@@ -776,6 +776,8 @@ _mesa_test_framebuffer_completeness(struct gl_context *ctx,
    GLint fixedSampleLocations = -1;
    GLint i;
    GLuint j;
+   bool layer_count_valid = false;
+   GLuint layer_count = 0, att_layer_count;
 
    assert(_mesa_is_user_fbo(fb));
 
@@ -948,8 +950,26 @@ _mesa_test_framebuffer_completeness(struct gl_context *ctx,
          fbo_incomplete("unsupported renderbuffer format", i);
          return;
       }
+
+      /* Check that layered rendering is consistent. */
+      att_layer_count = att->Layered ? att->Renderbuffer->Depth : 0;
+      if (!layer_count_valid) {
+         layer_count = att_layer_count;
+         layer_count_valid = true;
+      } else if (layer_count != att_layer_count) {
+         if (layer_count == 0 || att_layer_count == 0) {
+            fb->_Status = GL_FRAMEBUFFER_INCOMPLETE_LAYER_TARGETS;
+            fbo_incomplete("framebuffer attachment layer mode is inconsistent", i);
+         } else {
+            fb->_Status = GL_FRAMEBUFFER_INCOMPLETE_LAYER_COUNT_ARB;
+            fbo_incomplete("framebuffer attachment layer count is inconsistent", i);
+         }
+         return;
+      }
    }
 
+   fb->Layered = layer_count > 0;
+
    if (_mesa_is_desktop_gl(ctx) && !ctx->Extensions.ARB_ES2_compatibility) {
       /* Check that all DrawBuffers are present */
       for (j = 0; j < ctx->Const.MaxDrawBuffers; j++) {
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index eb8ec3a..fd8a7b1 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -2682,6 +2682,8 @@ struct gl_framebuffer
    struct gl_renderbuffer *_ColorDrawBuffers[MAX_DRAW_BUFFERS];
    struct gl_renderbuffer *_ColorReadBuffer;
 
+   GLboolean Layered;
+
    /** Delete this framebuffer */
    void (*Delete)(struct gl_framebuffer *fb);
 };
-- 
1.7.10.4