static void scale_and_bias_z	(	GLcontext *	ctx,
		GLuint	width,
		const GLfloat	depth[],
		GLuint	z[]
	)		`[static]`

Convert floating point Z values to integer Z values with pixel transfer's Z scale and bias.

Definition at line 410 of file s_copypix.c.

Referenced by copy_depth_pixels().

{
   const GLuint depthMax = ctx->DrawBuffer->_DepthMax;
   GLuint i;

   if (depthMax <= 0xffffff &&
       ctx->Pixel.DepthScale == 1.0 &&
       ctx->Pixel.DepthBias == 0.0) {
      /* no scale or bias and no clamping and no worry of overflow */
      const GLfloat depthMaxF = ctx->DrawBuffer->_DepthMaxF;
      for (i = 0; i < width; i++) {
         z[i] = (GLuint) (depth[i] * depthMaxF);
      }
   }
   else {
      /* need to be careful with overflow */
      const GLdouble depthMaxF = ctx->DrawBuffer->_DepthMaxF;
      for (i = 0; i < width; i++) {
         GLdouble d = depth[i] * ctx->Pixel.DepthScale + ctx->Pixel.DepthBias;
         d = CLAMP(d, 0.0, 1.0) * depthMaxF;
         if (d >= depthMaxF)
            z[i] = depthMax;
         else
            z[i] = (GLuint) d;
      }
   }
}

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