From 8477b99c8c683cf29000bb65a18912095d4aea69 Mon Sep 17 00:00:00 2001
From: couriersud <couriersud@arcor.de>
Date: Thu, 5 Mar 2015 02:44:07 +0100
Subject: [PATCH] Swap interval for baseline opengl. I can't test this. Neither
 virtualbox nor wine seem to support WGL Extensions. (nw)

---
 src/osd/modules/render/drawogl.c | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/src/osd/modules/render/drawogl.c b/src/osd/modules/render/drawogl.c
index 860d33ae1a8..328310ba9c6 100644
--- a/src/osd/modules/render/drawogl.c
+++ b/src/osd/modules/render/drawogl.c
@@ -204,6 +204,19 @@ public:
 		this->pfn_wglDeleteContext = (BOOL (WINAPI *)(HGLRC hglrc)) GetProcAddress(m_module, "wglDeleteContext");
 		this->pfn_wglMakeCurrent = (BOOL (WINAPI *)(HDC hdc, HGLRC hglrc)) GetProcAddress(m_module, "wglMakeCurrent");
 
+		this->pfn_wglGetExtensionsStringEXT = (const char *(WINAPI *) (void)) pfn_wglGetProcAddress("wglGetExtensionsStringEXT");
+
+		if (WGLExtensionSupported("WGL_EXT_swap_control"))
+		{
+			this->pfn_wglSwapIntervalEXT = (BOOL (WINAPI *) (int)) getProcAddress("wglSwapIntervalEXT");
+			this->pfn_wglGetSwapIntervalEXT = (int (WINAPI *) (void)) getProcAddress("wglGetSwapIntervalEXT");
+		}
+		else
+		{
+			pfn_wglSwapIntervalEXT = NULL;
+			pfn_wglGetSwapIntervalEXT = NULL;
+		}
+
 		m_hdc = GetDC(window);
 		if (!setupPixelFormat(m_hdc))
 		{
@@ -246,7 +259,10 @@ public:
 
 	virtual int SetSwapInterval(const int swap)
 	{
-		// FIXME: Missing!
+		if (this->pfn_wglSwapIntervalEXT != NULL)
+		{
+			this->pfn_wglSwapIntervalEXT(swap ? 1 : 0);
+		}
 		return 0;
 	}
 
@@ -300,6 +316,16 @@ private:
 	    return 0;
 	}
 
+	bool WGLExtensionSupported(const char *extension_name)
+	{
+	    //if (pfn_wglGetExtensionsStringEXT != NULL)
+	    //	printf("%s\n", this->pfn_wglGetExtensionsStringEXT());
+
+	    if (pfn_wglGetExtensionsStringEXT != NULL && strstr(pfn_wglGetExtensionsStringEXT(), extension_name) != NULL)
+	        return true;
+	    else
+	    	return false;
+	}
 
 	HGLRC m_context;
 	HWND m_window;
@@ -311,6 +337,10 @@ private:
 	BOOL (WINAPI *pfn_wglDeleteContext)(HGLRC hglrc);
 	BOOL (WINAPI *pfn_wglMakeCurrent)(HDC hdc, HGLRC hglrc);
 
+	const char *(WINAPI *pfn_wglGetExtensionsStringEXT) (void);
+	BOOL (WINAPI *pfn_wglSwapIntervalEXT) (int interval);
+	int (WINAPI * pfn_wglGetSwapIntervalEXT) (void);
+
 	static HMODULE m_module;
 };