51 lines
1.5 KiB
TypeScript
51 lines
1.5 KiB
TypeScript
import { mat2d, vec2 } from 'gl-matrix';
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import { Drawable } from '../drawable';
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import { DrawableDescriptor } from '../drawable-descriptor';
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/**
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* @category Drawable
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*/
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export class Circle extends Drawable {
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public static descriptor: DrawableDescriptor = {
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sdf: {
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shader: `
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uniform vec2 circleCenters[CIRCLE_COUNT];
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uniform float circleRadii[CIRCLE_COUNT];
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float circleMinDistance(vec2 target, out float colorIndex) {
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colorIndex = 2.0;
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float minDistance = 1000.0;
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for (int i = 0; i < CIRCLE_COUNT; i++) {
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float dist = distance(circleCenters[i], target) - circleRadii[i];
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minDistance = min(minDistance, dist);
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}
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return minDistance;
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}
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`,
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distanceFunctionName: 'circleMinDistance',
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},
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propertyUniformMapping: {
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center: 'circleCenters',
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radius: 'circleRadii',
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},
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uniformCountMacroName: 'CIRCLE_COUNT',
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shaderCombinationSteps: [0, 1, 2, 3, 8, 16],
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empty: new Circle(vec2.fromValues(0, 0), 0),
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};
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constructor(public center: vec2, public radius: number) {
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super();
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}
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public minDistance(target: vec2): number {
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return vec2.dist(this.center, target) - this.radius;
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}
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protected getObjectToSerialize(transform2d: mat2d, transform1d: number): any {
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return {
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center: vec2.transformMat2d(vec2.create(), this.center, transform2d),
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radius: this.radius * transform1d,
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};
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}
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}
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