mesa: replace gl_context->Multisample._Enabled with _mesa_is_multisample_enabled.

This removes any dependency on driver validation of the number of
framebuffer samples.

Signed-off-by: Bas Nieuwenhuizen <[email protected]>
Reviewed-by: Edward O'Callaghan <[email protected]>
Reviewed-by: Marek Olšák <[email protected]>
Tested-by: Brian Paul <[email protected]>

4 files changed, 22 insertions, 18 deletions

diff --git a/src/mesa/main/framebuffer.c b/src/mesa/main/framebuffer.c
index d18166d528e..f69dc6cb3e6 100644
--- a/src/mesa/main/framebuffer.c
+++ b/src/mesa/main/framebuffer.c
@@ -983,3 +983,22 @@ _mesa_is_front_buffer_drawing(const struct gl_framebuffer *fb)
    return (fb->_NumColorDrawBuffers >= 1 &&
            fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT);
 }
+
+static inline GLuint
+_mesa_geometric_nonvalidated_samples(const struct gl_framebuffer *buffer)
+{
+   return buffer->_HasAttachments ?
+      buffer->Visual.samples :
+      buffer->DefaultGeometry.NumSamples;
+}
+
+bool _mesa_is_multisample_enabled(const struct gl_context *ctx)
+{
+   /* The sample count may not be validated by the driver, but when it is set,
+    * we know that is in a valid range and no driver should ever validate a
+    * multisampled framebuffer to non-multisampled and vice-versa.
+    */
+   return ctx->Multisample.Enabled &&
+          ctx->DrawBuffer &&
+          _mesa_geometric_nonvalidated_samples(ctx->DrawBuffer) > 1;
+}
diff --git a/src/mesa/main/framebuffer.h b/src/mesa/main/framebuffer.h
index fa434d447ae..384f7498776 100644
--- a/src/mesa/main/framebuffer.h
+++ b/src/mesa/main/framebuffer.h
@@ -146,4 +146,7 @@ _mesa_is_front_buffer_reading(const struct gl_framebuffer *fb);
 extern bool
 _mesa_is_front_buffer_drawing(const struct gl_framebuffer *fb);
 
+extern bool
+_mesa_is_multisample_enabled(const struct gl_context *ctx);
+
 #endif /* FRAMEBUFFER_H */
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 5d8bfe4bb09..399f4508415 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -667,7 +667,6 @@ struct gl_list_attrib
 struct gl_multisample_attrib
 {
    GLboolean Enabled;
-   GLboolean _Enabled;   /**< true if Enabled and multisample buffer */
    GLboolean SampleAlphaToCoverage;
    GLboolean SampleAlphaToOne;
    GLboolean SampleCoverage;
diff --git a/src/mesa/main/state.c b/src/mesa/main/state.c
index 57f13411fdf..917ae4da023 100644
--- a/src/mesa/main/state.c
+++ b/src/mesa/main/state.c
@@ -344,20 +344,6 @@ update_frontbit(struct gl_context *ctx)
 
 
 /**
- * Update derived multisample state.
- */
-static void
-update_multisample(struct gl_context *ctx)
-{
-   ctx->Multisample._Enabled = GL_FALSE;
-   if (ctx->Multisample.Enabled &&
-       ctx->DrawBuffer &&
-       _mesa_geometric_samples(ctx->DrawBuffer) > 0)
-      ctx->Multisample._Enabled = GL_TRUE;
-}
-
-
-/**
  * Update the ctx->VertexProgram._TwoSideEnabled flag.
  */
 static void
@@ -450,9 +436,6 @@ _mesa_update_state_locked( struct gl_context *ctx )
    if (new_state & _NEW_PIXEL)
       _mesa_update_pixel( ctx, new_state );
 
-   if (new_state & (_NEW_MULTISAMPLE | _NEW_BUFFERS))
-      update_multisample( ctx );
-
    /* ctx->_NeedEyeCoords is now up to date.
     *
     * If the truth value of this variable has changed, update for the