Mesa (master): mesa: Add helper function _mesa_is_alpha_test_enabled()

[Anuj Phogat]

Module: Mesa
Branch: master
Commit: 0295c792b4b47865ddf7760ebe2980fc6f7a536b
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=0295c792b4b47865ddf7760ebe2980fc6f7a536b

Author: Anuj Phogat <anuj.phogat at gmail.com>
Date:   Tue Oct 25 11:55:44 2016 -0700

mesa: Add helper function _mesa_is_alpha_test_enabled()

Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
Reviewed-by: Brian Paul <brianp at vmware.com>
Reviewed-by: Ben Widawsky <ben at bwidawsk.net>

---

 src/mesa/main/framebuffer.c | 11 +++++++++++
 src/mesa/main/framebuffer.h |  3 +++
 2 files changed, 14 insertions(+)

diff --git a/src/mesa/main/framebuffer.c b/src/mesa/main/framebuffer.c
index e1505fa..361ed66 100644
--- a/src/mesa/main/framebuffer.c
+++ b/src/mesa/main/framebuffer.c
@@ -1005,3 +1005,14 @@ _mesa_is_multisample_enabled(const struct gl_context *ctx)
           ctx->DrawBuffer &&
           _mesa_geometric_nonvalidated_samples(ctx->DrawBuffer) > 1;
 }
+
+/**
+ * Is alpha testing enabled and applicable to the currently bound
+ * framebuffer?
+ */
+bool
+_mesa_is_alpha_test_enabled(const struct gl_context *ctx)
+{
+   bool buffer0_is_integer = ctx->DrawBuffer->_IntegerBuffers & 0x1;
+   return (ctx->Color.AlphaEnabled && !buffer0_is_integer);
+}
diff --git a/src/mesa/main/framebuffer.h b/src/mesa/main/framebuffer.h
index 384f749..a6adb1c 100644
--- a/src/mesa/main/framebuffer.h
+++ b/src/mesa/main/framebuffer.h
@@ -149,4 +149,7 @@ _mesa_is_front_buffer_drawing(const struct gl_framebuffer *fb);
 extern bool
 _mesa_is_multisample_enabled(const struct gl_context *ctx);
 
+extern bool
+_mesa_is_alpha_test_enabled(const struct gl_context *ctx);
+
 #endif /* FRAMEBUFFER_H */