User Guide

  • 2020.3
  • 07/10/2020
  • Public Content
Contents

See Also

Use this override mode to visualize the overall complexity of your scene, highlighting potential areas to investigate for optimization. If a scene renders only a few objects, the amount of overdraw is usually low and no further optimization is required. If a scene has many overlapping objects, or objects with semitransparent textures (such as smoke, fog, or water), this typically results in a high load on the graphics card and therefore lower frame rates.
The
Overdraw Visualization
mode fills the frame buffer with a brightness value according to the number of times each pixel is drawn. The brightness of a pixel indicates the number of times each pixel was "touched" by a draw call or clear call. The lighter the pixel, the more times that pixel has been overdrawn, which typically means the relative cost of rendering that pixel is fairly high. Conversely, darker pixels indicate relatively efficient rendering. Bright areas of the screen may provide optimization opportunities such as culling primitives prior to rendering them, altering the draw order (so that z-buffer tests will reject many primitives prior to rendering them with an expensive pixel shader), or using other level-of-detail optimizations that simplify the complexity of the scene.
If the overdraw value in one or more areas of the scene is high, use the Graphics Frame Analyzer with the Pixel History feature with overdraw mode enabled - this can help you understand which events are being rendered into each pixel and help pinpoint optimization opportunities.
NOTE
The current implementation may not take into account overdraw in off-screen render target surfaces, if such surfaces are used as a texture with a non-full screen quad draw call. However, if an off-screen render target is used as a full screen quad, all accumulated overdrawn pixels will be visualized.
Normal Picture
Overdraw Visualization
 

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804