38 lines
719 B
Go
38 lines
719 B
Go
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package canvas
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import (
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"syscall/js"
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)
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// Canvas represents an HTML5 Canvas object.
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type Canvas struct {
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Value js.Value
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ctx2d js.Value
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}
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// GetCanvas gets an HTML5 Canvas object from the DOM.
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func GetCanvas(id string) Canvas {
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canvasEl := js.Global().Get("document").Call("getElementById", id)
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canvas2d := canvasEl.Call("getContext", "2d")
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c := Canvas{
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Value: canvasEl,
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ctx2d: canvas2d,
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}
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canvasEl.Set("width", c.ClientW())
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canvasEl.Set("height", c.ClientH())
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return c
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}
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// ClientW returns the client width.
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func (c Canvas) ClientW() int {
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return c.Value.Get("clientWidth").Int()
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}
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// ClientH returns the client height.
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func (c Canvas) ClientH() int {
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return c.Value.Get("clientHeight").Int()
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}
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