goban/build/src/Goban/canvas_utils.d.ts

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/** On iOS devices they limit the number of canvases we create to a a very low
 * number and so sometimes we'll exhaust that limit. When this happens, we this
 * method will detect that and call our GobanCore.canvasAllocationErrorHandler
 * hook. On OGS we'll reload the page in that hook after logging the error.
 *
 * If string dimensions are used we'll use setAttribute, if numbers are used
 * we'll set the canvas .width and .height parameter. This is for device
 * scaling considerations when the given dimensions are scaled on HDPI devices.
 */
export declare function allocateCanvasOrError(width?: number | string, height?: number | string): HTMLCanvasElement;
/**
 * Validates that a canvas was created successfully and a 2d context can be
 * allocated for it. If not, we call the GobanCore.canvasAllocationErrorHandler
 * hook.
 */
export declare function validateCanvas(canvas: HTMLCanvasElement | null, err?: Error, width?: number | string, height?: number | string): boolean;
export declare function createDeviceScaledCanvas(width: number, height: number): HTMLCanvasElement;
export declare function resizeDeviceScaledCanvas(canvas: HTMLCanvasElement, width: number, height: number): HTMLCanvasElement;
export declare function deviceCanvasScalingRatio(): number;
/** Returns `{x,y}` of the event relative to the event target */
export declare function getRelativeEventPosition(event: TouchEvent | MouseEvent, target?: HTMLElement): {
    x: number;
    y: number;
};
export declare function elementOffset(element: HTMLElement): {
    top: number;
    left: number;
};