Graphics Reference
In-Depth Information
Figure 14-12
Checkerboard Procedural Texture
As you can see, this was really easy to implement. We do see quite a
bit of aliasing, which is never acceptable. With a texture checkerboard
image, aliasing issues are overcome by using mipmapping and applying
preferably a trilinear or bilinear filter. We now look at how to render an
anti-aliased checkerboard pattern.
In
Advanced RenderMan: Creating CGI for Motion Pictures
, Anthony Apodaca
and Larry Gritz give a very thorough explanation of how to implement
analytic anti-aliasing of procedural textures. We use the techniques
described in this topic to implement our anti-aliased checker fragment
shader. Example 14-21 describes the anti-aliased checker fragment shader
code from the CheckerAA.rfx PVR_Shaman workspace in
Chapter_14/
PVR_ProceduralTextures
.
Example 14-21
Anti-Aliased Checker Fragment Shader
#version 300 es
precision mediump float;
uniform int u_frequency;
in vec2 v_st;
layout(location = 0) out vec4 outColor;
(continues)
