33 lines
696 B
Go
33 lines
696 B
Go
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package collision
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import (
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"git.kirsle.net/apps/doodle/lib/render"
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)
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// IndexTuple holds two integers used as array indexes.
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type IndexTuple [2]int
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// BetweenBoxes checks if there is a collision between any
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// two bounding rectangles.
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//
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// This returns a generator that spits out indexes of the
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// intersecting boxes.
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func BetweenBoxes(boxes []render.Rect) chan IndexTuple {
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generator := make(chan IndexTuple)
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go func() {
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// Outer loop: test each box for intersection with the others.
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for i, box := range boxes {
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for j := i + 1; j < len(boxes); j++ {
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if box.Intersects(boxes[j]) {
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generator <- IndexTuple{i, j}
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}
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}
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}
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close(generator)
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}()
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return generator
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}
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