Noah Petherbridge
af67b20d9b
* Initial WebAssembly build target for Doodle in the wasm/ folder.
* Add a new render.Engine implementation, lib/render/canvas that uses
the HTML 5 Canvas API instead of SDL2 for the WebAssembly target.
* Ported the basic DrawLine(), DrawBox() etc. functions from SDL2 to
Canvas context2d API.
* Fonts are handled with CSS embedded fonts named after the font
filename and defined in wasm/index.html
* `make wasm` builds the WASM program, and `make wasm-serve` runs a dev
Go server that hosts the WASM file for development. The server also
watches the dev tree for *.go files and rebuilds the WASM binary
automatically on change.
* This build "basically" runs the game. UI and fonts all work and mouse
movements and clicks are detected. No wallpaper support yet or texture
caching (which will crash the game as soon as you click and draw a
pixel in your map!)
38 lines
719 B
Go
38 lines
719 B
Go
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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