24 lines
660 B
TypeScript
24 lines
660 B
TypeScript
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import { env } from '../env';
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import { resolveInput } from './resolveInput';
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export function getContext2dOrThrow(canvasArg: string | HTMLCanvasElement | CanvasRenderingContext2D): CanvasRenderingContext2D {
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const { Canvas, CanvasRenderingContext2D } = env.getEnv()
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if (canvasArg instanceof CanvasRenderingContext2D) {
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return canvasArg
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}
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const canvas = resolveInput(canvasArg)
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if (!(canvas instanceof Canvas)) {
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throw new Error('resolveContext2d - expected canvas to be of instance of Canvas')
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}
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const ctx = canvas.getContext('2d')
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if (!ctx) {
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throw new Error('resolveContext2d - canvas 2d context is null')
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}
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return ctx
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}
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