Mesa (master): radeon: Invert front face winding when rendering to FBO.

[Michel Dänzer]

Module: Mesa
Branch: master
Commit: 60e60bb3026a269fefe1cfd3312fdf3a7e4c595f
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=60e60bb3026a269fefe1cfd3312fdf3a7e4c595f

Author: Michel Dänzer <daenzer at vmware.com>
Date:   Tue Jul 14 08:00:49 2009 +0200

radeon: Invert front face winding when rendering to FBO.

Fixes fgl_glxgears and progs/demos/fbotexture after pressing 'c'.

Tested with r300, radeon and r200 compile tested only.

---

 src/mesa/drivers/dri/r200/r200_state.c     |    4 ++++
 src/mesa/drivers/dri/r300/r300_state.c     |    4 ++++
 src/mesa/drivers/dri/radeon/radeon_state.c |    4 ++++
 3 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/src/mesa/drivers/dri/r200/r200_state.c b/src/mesa/drivers/dri/r200/r200_state.c
index c7c1a39..5a6fd20 100644
--- a/src/mesa/drivers/dri/r200/r200_state.c
+++ b/src/mesa/drivers/dri/r200/r200_state.c
@@ -574,6 +574,10 @@ static void r200FrontFace( GLcontext *ctx, GLenum mode )
    R200_STATECHANGE( rmesa, tcl );
    rmesa->hw.tcl.cmd[TCL_UCP_VERT_BLEND_CTL] &= ~R200_CULL_FRONT_IS_CCW;
 
+   /* Winding is inverted when rendering to FBO */
+   if (ctx->DrawBuffer && ctx->DrawBuffer->Name)
+      mode = (mode == GL_CW) ? GL_CCW : GL_CW;
+
    switch ( mode ) {
    case GL_CW:
       rmesa->hw.set.cmd[SET_SE_CNTL] |= R200_FFACE_CULL_CW;
diff --git a/src/mesa/drivers/dri/r300/r300_state.c b/src/mesa/drivers/dri/r300/r300_state.c
index 4d504d1..12fbf28 100644
--- a/src/mesa/drivers/dri/r300/r300_state.c
+++ b/src/mesa/drivers/dri/r300/r300_state.c
@@ -434,6 +434,10 @@ static void r300UpdateCulling(GLcontext * ctx)
 		break;
 	}
 
+	/* Winding is inverted when rendering to FBO */
+	if (ctx->DrawBuffer && ctx->DrawBuffer->Name)
+		val ^= R300_FRONT_FACE_CW;
+
 	R300_STATECHANGE(r300, cul);
 	r300->hw.cul.cmd[R300_CUL_CULL] = val;
 }
diff --git a/src/mesa/drivers/dri/radeon/radeon_state.c b/src/mesa/drivers/dri/radeon/radeon_state.c
index 78f7e9d..0d1728b 100644
--- a/src/mesa/drivers/dri/radeon/radeon_state.c
+++ b/src/mesa/drivers/dri/radeon/radeon_state.c
@@ -458,6 +458,10 @@ static void radeonFrontFace( GLcontext *ctx, GLenum mode )
    RADEON_STATECHANGE( rmesa, tcl );
    rmesa->hw.tcl.cmd[TCL_UCP_VERT_BLEND_CTL] &= ~RADEON_CULL_FRONT_IS_CCW;
 
+   /* Winding is inverted when rendering to FBO */
+   if (ctx->DrawBuffer && ctx->DrawBuffer->Name)
+      mode = (mode == GL_CW) ? GL_CCW : GL_CW;
+
    switch ( mode ) {
    case GL_CW:
       rmesa->hw.set.cmd[SET_SE_CNTL] |= RADEON_FFACE_CULL_CW;