Mali GPU User Interface Engine Application Development Guide

Tutorial on Drawing 3D ShapesoLight0Dir = light0position - oPos;tLight0Dir = oLight0Dir * tangentSpace;oLight1Dir = light1position - oPos;tLight1Dir = oLight1Dir * tangentSpace;}tViewDir = oViewDir * tangentSpace;7. Example 4-64 shows the fragment shader code for the environment:Example 4-64 Environment fragment shader lightshow.frag...varying vec3 oPos;varying vec3 tViewDir;varying vec2 outTexcoord;varying vec3 oLight0Dir;varying vec3 tLight0Dir;varying vec3 oLight1Dir;varying vec3 tLight1Dir;uniform sampler2D diffuseMap;uniform sampler2D normalMap;uniform sampler2D glossMap;uniform vec3 cameraPosition;uniform vec3 light0color;uniform vec3 light1color;uniform vec3 light2color;uniform vec3 light0position;const float pi = 3.1415;uniform vec3 shadow_info[2];const float soft_shadow_eps = 0.015;// calculate how the light source intersects the columnfloat intersectRayCylinder(vec2 ray_origin, vec3 shadow_info){const float scale_factor = (0.5/pi);float offset = shadow_info.x;float light_dist = shadow_info.y;float limit = shadow_info.z;vec2 light_pixel = ray_origin.xy - light0position.xy;float angle = fract(atan(light_pixel.y, light_pixel.x)*scale_factor - offset);float adjusted_angle = abs(angle - 0.5);}return smoothstep(limit, limit+soft_shadow_eps, adjusted_angle) *float(light_dist < length(light_pixel));// is this point in shadowfloat getShadow(vec2 oPos){float shadow = 0.0;shadow = max(shadow, intersectRayCylinder(oPos, shadow_info[0]));shadow = max(shadow, intersectRayCylinder(oPos, shadow_info[1]));ARM DUI 0527A-02a Copyright © 2010 ARM. All rights reserved. 4-52ID070710Non-Confidential - Draft - Beta