Properly handle alpha to coverage state in non-cloning codepath

Also improve the alpha to coverage handlign in the helpers by using
a single function rather than two.

This removes GL errors about bad glFace enum values (caused by bad
handlign of alpha to coverage in switch statement, which led to a
FrontFace state being created with bad data).

Change-Id: I832d92fcb07134525f421d3a3b4d12e9f5f6428c
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

1 files changed, 2 insertions, 7 deletions

diff --git a/src/render/graphicshelpers/graphicscontext.cpp b/src/render/graphicshelpers/graphicscontext.cpp
index 3d387be66..1600f24e6 100644
--- a/src/render/graphicshelpers/graphicscontext.cpp
+++ b/src/render/graphicshelpers/graphicscontext.cpp
@@ -832,14 +832,9 @@ void GraphicsContext::buildUniformBuffer(const QVariant &v, const ShaderUniform
     m_glHelper->buildUniformBuffer(v, description, buffer);
 }
 
-void GraphicsContext::enableAlphaCoverage()
+void GraphicsContext::setAlphaCoverageEnabled(bool enabled)
 {
-    m_glHelper->enableAlphaCoverage();
-}
-
-void GraphicsContext::disableAlphaCoverage()
-{
-    m_glHelper->disableAlphaCoverage();
+    m_glHelper->setAlphaCoverageEnabled(enabled);
 }
 
 GLuint GraphicsContext::boundFrameBufferObject()