Hardware Implementation of Phong Shading Using Spherical Interpolation
نویسندگان
چکیده
Computer image generation systems often represent curved surfaces as a mesh of planar polygons that are shaded to restore a smooth appearance. In software rendering Phong shading has been one of the most successful algorithms, because it can realistically handle specular materials. Since it requires the rendering equation to be evaluated for each pixel, its hardware support poses problems. This paper presents a reformulation of the Phong shading algorithm that is based on interpolating on the surface of spheres. The reformulation results in simpler formulae that can be directly implemented in hardware. The software simulations and the VHDL description of the shading hardware are also presented.
منابع مشابه
Efficient Point-Based Rendering Using Image Reconstruction
Image-space reconstruction of continuous surfaces from scattered one-pixel projections of points is known to potentially offer an advantageous time complexity compared to surface splatting techniques. We propose a new algorithm for hardware-accelerated image-space reconstruction using pull-push interpolation and present an efficient GPU implementation. Compared to published image-space reconstr...
متن کاملQuadratic Shading and its Hardware Implementation
Rendering systems often represent curved surfaces as a mesh of planar polygons that are shaded to restore a smooth appearance. Gouraud shading uses linear color interpolation and its hardware implementation is relatively easy, but it handles specular highlights incorrectly and introduces annoying artifacts called Mach banding over the edges of the polygon mesh. In software rendering Phong shadi...
متن کاملA Real Time Rendering System with Normal Vector Shading
graphics workstations have rendering performances of more than one million polygons per second in This paper presents a graphics workstation for real conjunction with hardware supported transparency, time display of Phong shaded polygons. The applied anti-aliasing, perspective texture mapping, image shading method is based on normal vector compositing, etc. In spite of the fact that great stri...
متن کاملShading by Quaternion Interpolation
The purpose of this paper is to show that linear interpolation of quaternions can be used for true Phong shading and also for related techniques that use frames, like bump mapping and anisotropic shading. Quaternion interpolation for shading has not been proposed in literature and the reason might be that it turns out to be mostly of academic interest, and it will here be explained why. Further...
متن کاملImproved Specular Highlights With Adaptive Shading
the interior pixel colors from the vertex colors. Phong . Gouraud shading and Phong shading are widely used interpolation methods to render a polygon mesh of a curved surface. When an illumination equation has a specular reflection term, Phong shading produces more realistic results than does Gouraud shading. The specular highlights produced by Phong shading give visual information about surfac...
متن کامل