From aa90e6848f3200433cabc3fea2c87df0b1f767c5 Mon Sep 17 00:00:00 2001
From: Dries Harnie <dries@harnie.be>
Date: Mon, 21 Apr 2014 11:45:26 +0200
Subject: [PATCH] GRAPHICS: Only use packed depth-stencil framebuffer if
 extensions allow it

---
 graphics/opengles2/framebuffer.cpp  | 39 +++++++++++++++++++++++------
 graphics/opengles2/framebuffer.h    |  2 +-
 graphics/opengles2/system_headers.h |  2 --
 3 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/graphics/opengles2/framebuffer.cpp b/graphics/opengles2/framebuffer.cpp
index 3f257bb7fad..561abeb0549 100644
--- a/graphics/opengles2/framebuffer.cpp
+++ b/graphics/opengles2/framebuffer.cpp
@@ -25,21 +25,44 @@
 #if defined(USE_GLES2) || defined(USE_OPENGL_SHADERS)
 
 #include "graphics/opengles2/framebuffer.h"
+#include "graphics/opengles2/extensions.h"
+
+#ifdef USE_GLES2
+#define GL_DEPTH24_STENCIL8 GL_DEPTH24_STENCIL8_OES
+#endif
 
 namespace Graphics {
 
+static bool usePackedBuffer() {
+#ifdef USE_GLES2
+	return Graphics::isExtensionSupported("GL_OES_packed_depth_stencil");
+#endif
+	return true;
+}
+
 FrameBuffer::FrameBuffer(GLuint texture_name, uint width, uint height, uint texture_width, uint texture_height) : _colorTexture(texture_name), _width(width), _height(height) {
 	glGenFramebuffers(1, &_frameBuffer);
-	glGenRenderbuffers(1, &_depthRenderBuffer);
-
-	glBindRenderbuffer(GL_RENDERBUFFER, _depthRenderBuffer);
-	glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, texture_width, texture_height);
-	glBindRenderbuffer(GL_RENDERBUFFER, 0);
+	glGenRenderbuffers(2, &_renderBuffers[0]);
 
 	glBindFramebuffer(GL_FRAMEBUFFER, _frameBuffer);
 	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture_name, 0);
-	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, _depthRenderBuffer);
-	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, _depthRenderBuffer);
+
+if (usePackedBuffer()) {
+	glBindRenderbuffer(GL_RENDERBUFFER, _renderBuffers[0]);
+	glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, texture_width, texture_height);
+	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, _renderBuffers[0]);
+	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, _renderBuffers[0]);
+	glBindRenderbuffer(GL_RENDERBUFFER, 0);
+} else {
+	glBindRenderbuffer(GL_RENDERBUFFER, _renderBuffers[0]);
+	glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT16, texture_width, texture_height);
+	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, _renderBuffers[0]);
+
+	glBindRenderbuffer(GL_RENDERBUFFER, _renderBuffers[1]);
+	glRenderbufferStorage(GL_RENDERBUFFER, GL_STENCIL_INDEX8, texture_width, texture_height);
+	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, _renderBuffers[1]);
+	glBindRenderbuffer(GL_RENDERBUFFER, 0);
+}
 
 	glBindFramebuffer(GL_FRAMEBUFFER, _frameBuffer);
 	GLenum status=glCheckFramebufferStatus(GL_FRAMEBUFFER);
@@ -51,7 +74,7 @@ FrameBuffer::FrameBuffer(GLuint texture_name, uint width, uint height, uint text
 }
 
 FrameBuffer::~FrameBuffer() {
-	glDeleteRenderbuffers(1, &_depthRenderBuffer);
+	glDeleteRenderbuffers(2, &_renderBuffers[0]);
 	glDeleteFramebuffers(1, &_frameBuffer);
 }
 
diff --git a/graphics/opengles2/framebuffer.h b/graphics/opengles2/framebuffer.h
index 45b1d5e406a..965d65da3f5 100644
--- a/graphics/opengles2/framebuffer.h
+++ b/graphics/opengles2/framebuffer.h
@@ -39,7 +39,7 @@ public:
 
 private:
 	GLuint _colorTexture;
-	GLuint _depthRenderBuffer;
+	GLuint _renderBuffers[2];
 	GLuint _frameBuffer;
 	uint _width, _height;
 };
diff --git a/graphics/opengles2/system_headers.h b/graphics/opengles2/system_headers.h
index 45f0da2c76d..95d6a25ff65 100644
--- a/graphics/opengles2/system_headers.h
+++ b/graphics/opengles2/system_headers.h
@@ -37,8 +37,6 @@
 #endif
 #undef GL_GLEXT_PROTOTYPES
 
-#define GL_DEPTH24_STENCIL8 GL_DEPTH24_STENCIL8_OES
-
 #ifndef GL_BGRA
 #	define GL_BGRA GL_BGRA_EXT
 #endif