handle BGRA8; nVidia cards prefer this format

stepmania/src/RageDisplay.cpp

@@ -58,6 +58,7 @@ Preference<float> g_fFrameLimitPercent( "FrameLimitPercent", 0.0f );
 
 static const char *PixelFormatNames[] = {
 	"RGBA8",
+	"BGRA8",
 	"RGBA4",
 	"RGB5A1",
 	"RGB5",

stepmania/src/RageDisplay.h

@@ -54,6 +54,7 @@ protected:
 enum PixelFormat
 {
 	PixelFormat_RGBA8,
+	PixelFormat_BGRA8,
 	PixelFormat_RGBA4,
 	PixelFormat_RGB5A1,
 	PixelFormat_RGB5,

stepmania/src/RageDisplay_D3D.cpp

@@ -130,6 +130,8 @@ static const RageDisplay::PixelFormatDesc PIXEL_FORMAT_DESC[NUM_PixelFormat] = {
 		  0x0000FF00,
 		  0x000000FF,
 		  0xFF000000 }
+	}, {
+		0, { 0,0,0,0 }
 	}, {
 		/* A4R4G4B4 */
 		16,
@@ -177,6 +179,7 @@ static const RageDisplay::PixelFormatDesc PIXEL_FORMAT_DESC[NUM_PixelFormat] = {
 static D3DFORMAT D3DFORMATS[NUM_PixelFormat] = 
 {
 	D3DFMT_A8R8G8B8,
+	D3DFMT_UNKNOWN,
 	D3DFMT_A4R4G4B4,
 	D3DFMT_A1R5G5B5,
 	D3DFMT_X1R5G5B5,

stepmania/src/RageDisplay_OGL.cpp

@@ -73,6 +73,13 @@ static RageDisplay::PixelFormatDesc PIXEL_FORMAT_DESC[NUM_PixelFormat] = {
 		  0x00FF0000,
 		  0x0000FF00,
 		  0x000000FF }
+	}, {
+		/* B8G8R8A8 */
+		32,
+		{ 0x0000FF00,
+		  0x00FF0000,
+		  0xFF000000,
+		  0x000000FF }
 	}, {
 		/* R4G4B4A4 */
 		16,
@@ -149,6 +156,11 @@ struct GLPixFmtInfo_t {
 		GL_RGBA8,
 		GL_RGBA,
 		GL_UNSIGNED_BYTE,
+	}, {
+		/* R8G8B8A8 */
+		GL_RGBA8,
+		GL_BGRA,
+		GL_UNSIGNED_BYTE,
 	}, {
 		/* B4G4R4A4 */
 		GL_RGBA4,