mesa: Add new functions and enums required by GL_ARB_sample_shading

New functions added by GL_ARB_sample_shading:
glMinSampleShadingARB()

New enums:
GL_SAMPLE_SHADING_ARB
GL_MIN_SAMPLE_SHADING_VALUE_ARB

V2: Update comments.
    Create new GL4x.xml.
    Remove redundant code in get.c.
    Update the API_XML list in Makefile.am.
    Add extra_gl40_ARB_sample_shading predicate to get.c.

V3:
   Fix make check failure.
   Add checks for desktop GL.
   Use GLfloat in place of GLclampf in glMinSampleShading().
Signed-off-by: Anuj Phogat <[email protected]>
Reviewed-by: Ken Graunke <[email protected]>

1 files changed, 18 insertions, 0 deletions

diff --git a/src/mesa/main/multisample.c b/src/mesa/main/multisample.c
index bd97c50960e..599cdee7407 100644
--- a/src/mesa/main/multisample.c
+++ b/src/mesa/main/multisample.c
@@ -119,6 +119,24 @@ _mesa_SampleMaski(GLuint index, GLbitfield mask)
    ctx->Multisample.SampleMaskValue = mask;
 }
 
+/**
+ * Called via glMinSampleShadingARB
+ */
+void GLAPIENTRY
+_mesa_MinSampleShading(GLclampf value)
+{
+   GET_CURRENT_CONTEXT(ctx);
+
+   if (!ctx->Extensions.ARB_sample_shading || !_mesa_is_desktop_gl(ctx)) {
+      _mesa_error(ctx, GL_INVALID_OPERATION, "glMinSampleShading");
+      return;
+   }
+
+   FLUSH_VERTICES(ctx, 0);
+
+   ctx->Multisample.MinSampleShadingValue = CLAMP(value, 0.0, 1.0);
+   ctx->NewState |= _NEW_MULTISAMPLE;
+}
 
 /**
  * Helper for checking a requested sample count against the limit