diff --git a/src/mesa/drivers/common/meta.c b/src/mesa/drivers/common/meta.c index ea9e417..fc28685 100644 --- a/src/mesa/drivers/common/meta.c +++ b/src/mesa/drivers/common/meta.c @@ -818,6 +818,21 @@ _mesa_meta_end(GLcontext *ctx) /** + * Convert Z from a normalized value in the range [0, 1] to an object-space + * Z coordinate in [-1, +1] so that drawing at the new Z position with the + * default/identity ortho projection results in the original Z value. + * Used by the meta-Clear, Draw/CopyPixels and Bitmap functions where the Z + * value comes from the clear value or raster position. + */ +static INLINE GLfloat +invert_z(GLfloat normZ) +{ + GLfloat objZ = 1.0 - 2.0 * normZ; + return objZ; +} + + +/** * One-time init for a temp_texture object. * Choose tex target, compute max tex size, etc. */ @@ -1438,7 +1453,7 @@ _mesa_meta_Clear(GLcontext *ctx, GLbitfield buffers) const GLfloat y0 = (GLfloat) ctx->DrawBuffer->_Ymin; const GLfloat x1 = (GLfloat) ctx->DrawBuffer->_Xmax; const GLfloat y1 = (GLfloat) ctx->DrawBuffer->_Ymax; - const GLfloat z = 1.0 - 2.0 * ctx->Depth.Clear; + const GLfloat z = invert_z(ctx->Depth.Clear); GLuint i; verts[0].x = x0; @@ -1544,7 +1559,7 @@ _mesa_meta_CopyPixels(GLcontext *ctx, GLint srcX, GLint srcY, const GLfloat dstY0 = (GLfloat) dstY; const GLfloat dstX1 = dstX + width * ctx->Pixel.ZoomX; const GLfloat dstY1 = dstY + height * ctx->Pixel.ZoomY; - const GLfloat z = ctx->Current.RasterPos[2]; + const GLfloat z = invert_z(ctx->Current.RasterPos[2]); verts[0].x = dstX0; verts[0].y = dstY0; @@ -1833,7 +1848,7 @@ _mesa_meta_DrawPixels(GLcontext *ctx, const GLfloat y0 = (GLfloat) y; const GLfloat x1 = x + width * ctx->Pixel.ZoomX; const GLfloat y1 = y + height * ctx->Pixel.ZoomY; - const GLfloat z = ctx->Current.RasterPos[2]; + const GLfloat z = invert_z(ctx->Current.RasterPos[2]); verts[0].x = x0; verts[0].y = y0; @@ -2036,7 +2051,7 @@ _mesa_meta_Bitmap(GLcontext *ctx, const GLfloat y0 = (GLfloat) y; const GLfloat x1 = (GLfloat) (x + width); const GLfloat y1 = (GLfloat) (y + height); - const GLfloat z = ctx->Current.RasterPos[2]; + const GLfloat z = invert_z(ctx->Current.RasterPos[2]); GLuint i; verts[0].x = x0;