void C4FoWAmbient::GetFragTransform(const FLOAT_RECT& vpRect, const C4Rect& clipRect, const C4Rect& outRect, float ambientTransform[6]) const
{
C4FragTransform trans;
// Invert Y coordinate
trans.Scale(1, -1);
trans.Translate(0, outRect.Hgt);
// Clip offset
trans.Translate(-clipRect.x, -clipRect.y);
// Clip normalization (0,0 -> 1,1)
trans.Scale(1.0f / clipRect.Wdt, 1.0f / clipRect.Hgt);
// Viewport normalization
trans.Scale(vpRect.right - vpRect.left, vpRect.bottom - vpRect.top);
// Viewport offset
trans.Translate(vpRect.left, vpRect.top);
// Landscape normalization
trans.Scale(1.0f / LandscapeX, 1.0f / LandscapeY);
// Extract matrix
trans.Get2x3(ambientTransform);
}
void C4FoWRegion::GetFragTransform(const C4Rect& clipRect, const C4Rect& outRect, float lightTransform[6]) const
{
const C4Rect& lightRect = getRegion();
const FLOAT_RECT& vpRect = ViewportRegion;
C4FragTransform trans;
// Clip offset
assert(outRect.Hgt >= clipRect.y + clipRect.Hgt);
trans.Translate(-clipRect.x, -(outRect.Hgt - clipRect.y - clipRect.Hgt));
// Clip normalization (0,0 -> 1,1)
trans.Scale(1.0f / clipRect.Wdt, 1.0f / clipRect.Hgt);
// Viewport/Landscape normalization
trans.Scale(vpRect.right - vpRect.left, vpRect.bottom - vpRect.top);
// Offset between viewport and light texture
trans.Translate(vpRect.left - lightRect.x, vpRect.top - lightRect.y);
// Light surface normalization
trans.Scale(1.0f / pSurface->Wdt, 1.0f / pSurface->Hgt);
// Light surface Y offset
trans.Translate(0.0f, 1.0f - (float)(lightRect.Hgt) / (float)pSurface->Hgt);
// Extract matrix
trans.Get2x3(lightTransform);
}