SemanticScuttle/includes/js/dojox/gfx3d/gradient.js

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if(!dojo._hasResource["dojox.gfx3d.gradient"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojox.gfx3d.gradient"] = true;
dojo.provide("dojox.gfx3d.gradient");
dojo.require("dojox.gfx3d.vector");
dojo.require("dojox.gfx3d.matrix");
(function(){
var dist = function(a, b){ return Math.sqrt(Math.pow(b.x - a.x, 2) + Math.pow(b.y - a.y, 2)); };
var N = 32;
dojox.gfx3d.gradient = function(model, material, center, radius, from, to, matrix){
// summary: calculate a cylindrical gradient
// model: dojox.gfx3d.lighting.Model: color model
// material: Object: defines visual properties
// center: Object: center of the cylinder's bottom
// radius: Number: radius of the cylinder
// from: Number: from position in radians
// to: Number: from position in radians
// matrix: dojox.gfx3d.Matrix3D: the cumulative transformation matrix
// tolerance: Number: tolerable diffirence in colors between gradient steps
var m = dojox.gfx3d.matrix, v = dojox.gfx3d.vector, mx = m.normalize(matrix),
f = m.multiplyPoint(mx, radius * Math.cos(from) + center.x, radius * Math.sin(from) + center.y, center.z),
t = m.multiplyPoint(mx, radius * Math.cos(to) + center.x, radius * Math.sin(to) + center.y, center.z),
c = m.multiplyPoint(mx, center.x, center.y, center.z), step = (to - from) / N, r = dist(f, t) / 2,
mod = model[material.type], fin = material.finish, pmt = material.color,
colors = [{offset: 0, color: mod.call(model, v.substract(f, c), fin, pmt)}];
for(var a = from + step; a < to; a += step){
var p = m.multiplyPoint(mx, radius * Math.cos(a) + center.x, radius * Math.sin(a) + center.y, center.z),
df = dist(f, p), dt = dist(t, p);
colors.push({offset: df / (df + dt), color: mod.call(model, v.substract(p, c), fin, pmt)});
}
colors.push({offset: 1, color: mod.call(model, v.substract(t, c), fin, pmt)});
return {type: "linear", x1: 0, y1: -r, x2: 0, y2: r, colors: colors};
};
})();
}