Noah Petherbridge
5893daba58
* Refactor texture caching in render.Engine:
* New interface method: NewTexture(filename string, image.Image)
* WASM immediately encodes the image to PNG and generates a JavaScript
`Image()` object to load it with a data URI and keep it in memory.
* SDL2 saves the bitmap to disk as it did before.
* WASM: deprecate the sessionStorage for holding image data. Session
storage methods panic if called. The image data is directly kept in
Go memory as a js.Value holding an Image().
* Shared Memory workaround: the level.Chunk.ToBitmap() function is where
chunk textures get cached, but it had no access to the render.Engine
used in the game. The `pkg/shmem` package holds global pointers to
common structures like the CurrentRenderEngine as a work-around.
* Also shmem.Flash() so Doodle can make its d.Flash() function
globally available, any sub-package can now flash text to the screen
regardless of source code location.
* JavaScript API for Doodads now has a global Flash() function
available.
* WASM: Handle window resize so Doodle can recompute its dimensions
instead of scaling/shrinking the view.
40 lines
842 B
Go
40 lines
842 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 js.Global().Get("window").Get("innerWidth").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 js.Global().Get("window").Get("innerHeight").Int()
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// return c.Value.Get("clientHeight").Int()
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}
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