void RenderLayersBaseProg::executePixel(float output[4], float x, float y, PixelSampler sampler)
{
#if 0
	const RenderData *rd = this->m_rd;

	int dx = 0, dy = 0;

	if (rd->mode & R_BORDER && rd->mode & R_CROP) {
		/* see comment in executeRegion describing coordinate mapping,
		 * here it simply goes other way around
		 */
		int full_width  = rd->xsch * rd->size / 100;
		int full_height = rd->ysch * rd->size / 100;

		dx = rd->border.xmin * full_width - (full_width - this->getWidth()) / 2.0f;
		dy = rd->border.ymin * full_height - (full_height - this->getHeight()) / 2.0f;
	}

	int ix = x - dx;
	int iy = y - dy;
#else
	int ix = x;
	int iy = y;
#endif

	if (this->m_inputBuffer == NULL || ix < 0 || iy < 0 || ix >= (int)this->getWidth() || iy >= (int)this->getHeight() ) {
		zero_v4(output);
	}
	else {
		doInterpolation(output, ix, iy, sampler);
	}
}
/* ******** Render Layers AO Operation ******** */
void RenderLayersAOOperation::executePixelSampled(float output[4], float x, float y, PixelSampler sampler)
{
	float *inputBuffer = this->getInputBuffer();
	if (inputBuffer == NULL) {
		zero_v3(output);
	}
	else {
		doInterpolation(output, x, y, sampler);
	}
	output[3] = 1.0f;
}
/* ******** Render Layers Alpha Operation ******** */
void RenderLayersAlphaProg::executePixelSampled(float output[4], float x, float y, PixelSampler sampler)
{
	float *inputBuffer = this->getInputBuffer();

	if (inputBuffer == NULL) {
		output[0] = 0.0f;
	}
	else {
		float temp[4];
		doInterpolation(temp, x, y, sampler);
		output[0] = temp[3];
	}
}
void RenderLayersProg::executePixelSampled(float output[4], float x, float y, PixelSampler sampler)
{
#if 0
  const RenderData *rd = this->m_rd;

  int dx = 0, dy = 0;

  if (rd->mode & R_BORDER && rd->mode & R_CROP) {
    /* see comment in executeRegion describing coordinate mapping,
     * here it simply goes other way around
     */
    int full_width = rd->xsch * rd->size / 100;
    int full_height = rd->ysch * rd->size / 100;

    dx = rd->border.xmin * full_width - (full_width - this->getWidth()) / 2.0f;
    dy = rd->border.ymin * full_height - (full_height - this->getHeight()) / 2.0f;
  }

  int ix = x - dx;
  int iy = y - dy;
#endif

#ifndef NDEBUG
  {
    const DataType data_type = this->getOutputSocket()->getDataType();
    int actual_element_size = this->m_elementsize;
    int expected_element_size;
    if (data_type == COM_DT_VALUE) {
      expected_element_size = 1;
    }
    else if (data_type == COM_DT_VECTOR) {
      expected_element_size = 3;
    }
    else if (data_type == COM_DT_COLOR) {
      expected_element_size = 4;
    }
    else {
      expected_element_size = 0;
      BLI_assert(!"Something horribly wrong just happened");
    }
    BLI_assert(expected_element_size == actual_element_size);
  }
#endif

  if (this->m_inputBuffer == NULL) {
    int elemsize = this->m_elementsize;
    if (elemsize == 1) {
      output[0] = 0.0f;
    }
    else if (elemsize == 3) {
      zero_v3(output);
    }
    else {
      BLI_assert(elemsize == 4);
      zero_v4(output);
    }
  }
  else {
    doInterpolation(output, x, y, sampler);
  }
}