Graphics Reference
In-Depth Information
4. The final step is to look at the fragment shader from step 2:
<script id="hexagonFragmentShader"
type="x-shader/x-fragment">
uniform sampler2D tDiffuse;
uniform vec2 center;
uniform float scale;
uniform vec2 texSize;
varying vec2 texCoord;
void main() {
vec2 tex = (texCoord * texSize -
center) / scale;
tex.y /= 0.866025404;
tex.x -= tex.y * 0.5;
vec2 a;
if (tex.x + tex.y - floor(tex.x) -
floor(tex.y) < 1.0)
a = vec2(floor(tex.x),
floor(tex.y));
else a = vec2(ceil(tex.x),
ceil(tex.y));
vec2 b = vec2(ceil(tex.x),
floor(tex.y));
vec2 c = vec2(floor(tex.x),
ceil(tex.y));
vec3 TEX = vec3(tex.x, tex.y, 1.0 -
tex.x - tex.y);
vec3 A = vec3(a.x, a.y, 1.0 - a.x -
a.y);
vec3 B = vec3(b.x, b.y, 1.0 - b.x -
b.y);
vec3 C = vec3(c.x, c.y, 1.0 - c.x -
c.y);
float alen = length(TEX - A);
float blen = length(TEX - B);
float clen = length(TEX - C);
vec2 choice;
if (alen < blen) {
