From 932e95c111118b643650d6643e47be0ddb5528a1 Mon Sep 17 00:00:00 2001 From: Henri Verbeet <hverbeet@codeweavers.com> Date: Mon, 8 Sep 2008 10:15:51 +0200 Subject: [PATCH] wined3d: Translate one pixel down after flipping for offscreen rendering. --- dlls/wined3d/state.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/dlls/wined3d/state.c b/dlls/wined3d/state.c index 61119954c77..61ccab66d5c 100644 --- a/dlls/wined3d/state.c +++ b/dlls/wined3d/state.c @@ -3905,19 +3905,32 @@ static void transform_projection(DWORD state, IWineD3DStateBlockImpl *stateblock divide by the Width/Height, so we need the half range(1.0) to translate by half a pixel. + Note that when rendering offscreen, we need to translate 1 pixel + (2/h in normalized device coordinates) down after doing the flip, + because of the way the viewport transformation works in OpenGL: + (-1,1) in normalized device coordinates corresponds to the upper + left corner of the upper left pixel in the viewport. (-1,-1) + corresponds to lower left corner of the lower left pixel in the + viewport. In other words, the upper left corner of the pixel + *below* the lower left pixel in the viewport. See also section + 2.11.1 "Controlling the Viewport" of the GL 2.1 spec. + The other fun is that d3d's output z range after the transformation is [0;1], but opengl's is [-1;1]. Since the z buffer is in range [0;1] for both, gl scales [-1;1] to [0;1]. This would mean that we end up in [0.5;1] and loose a lot of Z buffer precision and the clear values do not match in the z test. Thus scale [0;1] to [-1;1], so when gl undoes that we utilize the full z range */ - glTranslatef(1.0 / stateblock->viewport.Width, -1.0/ stateblock->viewport.Height, -1.0); - checkGLcall("glTranslatef (1.0 / width, -1.0 / height, -1.0)"); + if (stateblock->wineD3DDevice->render_offscreen) { /* D3D texture coordinates are flipped compared to OpenGL ones, so * render everything upside down when rendering offscreen. */ + glTranslatef(1.0 / stateblock->viewport.Width, 1.0 / stateblock->viewport.Height, -1.0); + checkGLcall("glTranslatef(1.0 / width, 1.0 / height, -1.0)"); glScalef(1.0, -1.0, 2.0); } else { + glTranslatef(1.0 / stateblock->viewport.Width, -1.0 / stateblock->viewport.Height, -1.0); + checkGLcall("glTranslatef(1.0 / width, -1.0 / height, -1.0)"); glScalef(1.0, 1.0, 2.0); } checkGLcall("glScalef"); @@ -4504,7 +4517,7 @@ static void vertexdeclaration(DWORD state, IWineD3DStateBlockImpl *stateblock, W */ if (useVertexShaderFunction) { device->posFixup[1] = device->render_offscreen ? -1.0 : 1.0; - device->posFixup[3] = -device->posFixup[1] / stateblock->viewport.Height; + device->posFixup[3] = -1.0 / stateblock->viewport.Height; } } @@ -4636,7 +4649,7 @@ static void viewport_miscpart(DWORD state, IWineD3DStateBlockImpl *stateblock, W static void viewport_vertexpart(DWORD state, IWineD3DStateBlockImpl *stateblock, WineD3DContext *context) { stateblock->wineD3DDevice->posFixup[2] = 1.0 / stateblock->viewport.Width; - stateblock->wineD3DDevice->posFixup[3] = -stateblock->wineD3DDevice->posFixup[1] / stateblock->viewport.Height; + stateblock->wineD3DDevice->posFixup[3] = -1.0 / stateblock->viewport.Height; if(!isStateDirty(context, STATE_TRANSFORM(WINED3DTS_PROJECTION))) { transform_projection(STATE_TRANSFORM(WINED3DTS_PROJECTION), stateblock, context); }