gsdx ogl: add the option force_texture_clear for test purpose

Might be completely useless.

1 => always clear framebuffers and textures to black (aka 0)
2 => always clear framebuffers and textures to red

plugins/GSdx/GSDeviceOGL.cpp

@@ -52,6 +52,7 @@ FILE* GSDeviceOGL::m_debug_gl_file = NULL;
 
 GSDeviceOGL::GSDeviceOGL()
 	: m_msaa(0)
+	, m_force_texture_clear(0)
 	, m_window(NULL)
 	, m_fbo(0)
 	, m_fbo_read(0)
@@ -150,15 +151,19 @@ GSTexture* GSDeviceOGL::CreateSurface(int type, int w, int h, bool msaa, int fmt
 	}
 
 	// NOTE: I'm not sure RenderTarget always need to be cleared. It could be costly for big upscale.
-	switch(type)
-	{
-		case GSTexture::RenderTarget:
-			ClearRenderTarget(t, 0);
-			break;
-		case GSTexture::DepthStencil:
-			ClearDepth(t, 0);
-			// No need to clear the stencil now.
-			break;
+	// FIXME: it will be more logical to do it in FetchSurface. This code is only called at first creation
+	//  of the texture. However we could reuse a deleted texture.
+	if (m_force_texture_clear == 0) {
+		switch(type)
+		{
+			case GSTexture::RenderTarget:
+				ClearRenderTarget(t, 0);
+				break;
+			case GSTexture::DepthStencil:
+				ClearDepth(t, 0);
+				// No need to clear the stencil now.
+				break;
+		}
 	}
 
 	return t;
@@ -166,7 +171,31 @@ GSTexture* GSDeviceOGL::CreateSurface(int type, int w, int h, bool msaa, int fmt
 
 GSTexture* GSDeviceOGL::FetchSurface(int type, int w, int h, bool msaa, int format)
 {
-	return GSDevice::FetchSurface(type, w, h, false, format);
+	GSTexture* t = GSDevice::FetchSurface(type, w, h, false, format);
+
+
+	if (m_force_texture_clear) {
+		GSVector4 red(1.0f, 0.0f, 0.0f, 1.0f);
+		switch(type)
+		{
+			case GSTexture::RenderTarget:
+				ClearRenderTarget(t, 0);
+				break;
+			case GSTexture::DepthStencil:
+				ClearDepth(t, 0);
+				// No need to clear the stencil now.
+				break;
+			case GSTexture::Texture:
+				if (m_force_texture_clear > 1)
+					static_cast<GSTextureOGL*>(t)->Clear((void*)&red);
+				else if (m_force_texture_clear)
+					static_cast<GSTextureOGL*>(t)->Clear(NULL);
+
+				break;
+		}
+	}
+
+	return t;
 }
 
 bool GSDeviceOGL::Create(GSWnd* wnd)
@@ -194,6 +223,8 @@ bool GSDeviceOGL::Create(GSWnd* wnd)
 	}
 #endif
 
+	m_force_texture_clear = theApp.GetConfigI("force_texture_clear");
+
 	// WARNING it must be done after the control setup (at least on MESA)
 	GL_PUSH("GSDeviceOGL::Create");
 

plugins/GSdx/GSDeviceOGL.h

@@ -398,6 +398,7 @@ public:
 
 	private:
 	uint32 m_msaa;				// Level of Msaa
+	int m_force_texture_clear;
 
 	static bool m_debug_gl_call;
 	static FILE* m_debug_gl_file;

plugins/GSdx/GSTextureOGL.cpp

@@ -29,9 +29,6 @@
 extern uint64 g_real_texture_upload_byte;
 #endif
 
-// FIXME find the optimal number of PBO
-#define PBO_POOL_SIZE 8
-
 // FIXME OGL4: investigate, only 1 unpack buffer always bound
 namespace PboPool {
 

plugins/GSdx/GSdx.cpp

@@ -275,6 +275,7 @@ GSdxApp::GSdxApp()
 	m_default_configuration["dump"]                                       = "0";
 	m_default_configuration["extrathreads"]                               = "2";
 	m_default_configuration["filter"]                                     = "2";
+	m_default_configuration["force_texture_clear"]                        = "0";
 	m_default_configuration["fxaa"]                                       = "0";
 	m_default_configuration["interlace"]                                  = "7";
 	m_default_configuration["large_framebuffer"]                          = "1";