47 lines
1.0 KiB
Go
47 lines
1.0 KiB
Go
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package chunk
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import (
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"math"
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)
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// HeightMap represents the height map of a chunk. It holds the y value of all the highest blocks in the chunk
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// that diffuse or obstruct light.
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type HeightMap []int16
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// At returns the height map value at a specific column in the chunk.
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func (h HeightMap) At(x, z uint8) int16 {
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return h[(uint16(x)<<4)|uint16(z)]
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}
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// Set changes the height map value at a specific column in the chunk.
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func (h HeightMap) Set(x, z uint8, val int16) {
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h[(uint16(x)<<4)|uint16(z)] = val
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}
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// HighestNeighbour returns the height map value of the highest directly neighbouring column of the x and z values
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// passed.
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func (h HeightMap) HighestNeighbour(x, z uint8) int16 {
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highest := int16(math.MinInt16)
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if x != 15 {
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if val := h.At(x+1, z); val > highest {
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highest = val
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}
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}
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if x != 0 {
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if val := h.At(x-1, z); val > highest {
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highest = val
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}
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}
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if z != 15 {
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if val := h.At(x, z+1); val > highest {
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highest = val
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}
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}
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if z != 0 {
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if val := h.At(x, z-1); val > highest {
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highest = val
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}
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}
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return highest
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}
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