Parallax occlusion mapping (abbreviated as POM ) is a software technique (technique) in three-dimensional computer graphics , an improved version of the parallax mapping technique. Parallax occlusion mapping is used to procedurally create a three-dimensional description of a textured surface using displacement maps ( en: Displacement mapping ) instead of directly generating new geometry. [1] The “Parallax occlusion mapping” technique can conditionally be called “ 2.5D ”, since it allows you to add three-dimensional complexity to textures without creating real three-dimensional graphic structures. Unlike simpler embossed texturing techniques like bump mapping , normal mapping, or parallax mapping , this technique allows you to correctly determine the perspective and self-shadowing in real time, without requiring the execution of GPU rendering passes to create the same effect with geometric calculations. [2]
Content
History of Creation and Use
The first work devoted to this technique appeared in 2004 on “ShaderX3”, its authors were Zoe Brawley ( Eng. Zoe Brawley ) and Natalia Tatarchuk ( Eng. Natalya Tatarchuk ). [1] Natalia Tatarchuk made a technology presentation at the 2005 SIGGRAPH event, which was held in Los Angeles in late summer 2005. [3] Further, the Parallax occlusion mapping technique was used by ATI in the Toy Shop Demo demonstration to present the capabilities of the third version of the shader model in the latest at that time Radeon X1800 graphics card. [four]
The first game engine to use Parallax occlusion mapping was CryEngine 2 from German developer Crytek , which was first used in the 2007 Crysis PC game . [5] This technology is also very heavily used in Futuremark’s popular 3DMark Vantage graphics benchmark . [6]
The Parallax occlusion mapping technique can be used in real-time interactive computer graphics ( graphics engines for computer games and other interactive applications), for offline rendering ( 3D graphics editors ), and for generating individual stereoscopic images. [7]
Description
Parallax Occlusion Mapping is an advanced and at the same time one of the most computationally complex varieties of Parallax Mapping. "Parallax Occlusion Mapping" is fully processed and executed on the graphics processor ( English GPU ) of the video card as a pixel shader. In fact, it is a form of local ray tracing (ray tracing) in a pixel shader. Ray tracing is used to determine heights and take into account texel visibility. In other words, this method can make it possible to create even greater relief depth at low polygon costs and the use of complex geometry. The disadvantage of this method is the low detailing of silhouettes and faces. It is possible to implement Parallax Occlusion Mapping as part of the API DirectX 9 SM3 functionality as a pixel shader, however, to obtain optimal performance, the video card must provide an appropriate level of speed for branching operations in the pixel shader. [five]
Notes
- ↑ 1 2 Brawley, Z., and Tatarchuk, N. 2004. Parallax Occlusion Mapping: Self-Shadowing, Perspective-Correct Bump Mapping Using Reverse Height Map Tracing. In ShaderX3: Advanced Rendering with DirectX and OpenGL, Engel, W., Ed., Charles River Media, pp. 135-154. https://books.google.ca/books?id=DgMSb_10l7IC&pg=PA135&dq=parallax+occlusion
- ↑ Dynamic Parallax Occlusion Mapping with Approximate Soft Shadows - Tatarchuk Archived on September 8, 2008.
- ↑ Sketches | Conference: SIGGRAPH 2005
- ↑ ATI Radeon X1800 Preview - TrustedReviews - TrustedReviews
- ↑ 1 2 Danil Gridasov. i3D-Quality - Under the microscope - April-May 2008 - DX9 vs DX10 in Crysis . iXBT.com (May 28, 2008). Date of treatment May 8, 2009. Archived March 11, 2012.
- ↑ Alexei Berillo. Futuremark 3DMark Vantage . iXBT.com (May 23, 2008). Date of treatment May 8, 2009. Archived March 31, 2012.
- ↑ Erik Benerdal. Generating stereoscopic images with parallax occlusion mapping . Scalari.net (April 22, 2008). Date of treatment May 8, 2009. Archived March 31, 2012.
Links
- gamedev.net. A Closer Look At Parallax Occlusion Mapping
- Parallax Occlusion Mapping in GLSL on sunandblackcat.com
- Dachsbacher, C., Tatarchuk, N. Prism Parallax Occlusion Mapping with Accurate Silhouette Generation as a .pdf
- Dachsbacher, C., Tatarchuk, N. Prism Parallax Occlusion Mapping with Accurate Silhouette Generation as a .mov (link not available)