30 lines
751 B
Go
30 lines
751 B
Go
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package engine
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// Box describes an axis-aligned rectangular prism.
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type Box struct {
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X, Y, Z int // coordinate of the left-top-farthest corner
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W, H, D int // width, height, depth
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}
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// IsoProjection translates an integer 3D coordinate into an integer 2D
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// coordinate.
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type IsoProjection struct {
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ZX, ZY int
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}
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// Project projects a 3D coordinate into 2D.
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// If ZX = 0, x is unchanged; similarly for ZY and y.
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// Otherwise, x becomes x + z/ZX and y becomes y + z/ZY.
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// This is because there's little reason for an isometric projection in a game
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// to exaggerate the Z position.
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func (π IsoProjection) Project(x, y, z int) (xp, yp int) {
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xp, yp = x, y
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if π.ZX != 0 {
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xp += z / π.ZX
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}
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if π.ZY != 0 {
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yp += z / π.ZY
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}
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return xp, yp
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}
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