Mali GPU User Interface Engine Application Development Guide

Tutorial on Constructing Custom Shadersvoid main(void){gl_FragColor = vec4(AMBIENT_LIGHT, 1.0) * COLOR +vec4(vDiffuse, 1.0) * COLOR +vec4(vSpecular, 1.0);}Lighting calculation in the fragment shaderThe vertex shader code in Example 6-29 passes more of the calculation to the fragment shader:Example 6-29 Specular lighting calculation in vertex shaderuniform mat4 WORLD_VIEW_PROJECTION;uniform mat3 WORLD;uniform vec3 LIGHT_POSITION;uniform vec3 CAMERA_POSITION;attribute vec4 POSITION;attribute vec3 NORMAL;varying vec3 vNormal;varying vec3 vLightVector;varying vec3 vCameraVector;void main(void){gl_Position = WORLD_VIEW_PROJECTION * POSITION;vec3 pos = WORLD * POSITION.xyz;}// No point in normalizing before the fragment shader as the normalization will// be offset by the interpolation anyway.vNormal = WORLD * NORMAL;vLightVector = LIGHT_POSITION - pos;vCameraVector = CAMERA_POSITION - pos;The fragment shader in Example 6-30 calculates the reflection vectors before combining thelight sources:Example 6-30 Fragment shader adds specular light to background lightuniform vec3 AMBIENT_LIGHT;uniform vec3 DIFFUSE_LIGHT;uniform vec3 SPECULAR_LIGHT;uniform vec4 COLOR;varying vec3 vNormal;varying vec3 vLightVector;varying vec3 vCameraVector;void main(void){vec3 normal = normalize(vNormal);ARM DUI 0527A-02a Copyright © 2010 ARM. All rights reserved. 6-22ID070710Non-Confidential - Draft - Beta