36 lines
841 B
Go
36 lines
841 B
Go
package backendbase
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import (
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"image"
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"image/color"
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)
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// Backend is used by the canvas to actually do the final
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// drawing. This enables the backend to be implemented by
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// various methods (OpenGL, but also other APIs or software)
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type Backend interface {
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ClearRect(x, y, w, h int)
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Clear(pts [4][2]float64)
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Fill(style *FillStyle, pts [][2]float64)
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LoadImage(img image.Image) (Image, error)
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DrawImage(dimg Image, sx, sy, sw, sh, dx, dy, dw, dh float64, alpha float64)
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}
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// FillStyle is the color and other details on how to fill
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type FillStyle struct {
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Color color.RGBA
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Blur float64
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// radialGradient *RadialGradient
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// linearGradient *LinearGradient
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// image *Image
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}
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type Image interface {
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Width() int
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Height() int
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Size() (w, h int)
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Delete()
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IsDeleted() bool
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Replace(src image.Image) error
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IsOpaque() bool
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}
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