00f14ce74f
Normally, I wouldn't have bothered with this, given that we already support the Vulkan 1.1 subgroup functionality, but a client asked for the legacy extensions.
30 lines
772 B
Plaintext
30 lines
772 B
Plaintext
#version 450
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#extension GL_ARB_shader_ballot : require
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layout (local_size_x = 64) in;
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layout (std430, binding = 0) buffer inputData
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{
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float inputDataArray[];
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};
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layout (std430, binding = 1) buffer outputData
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{
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float outputDataArray[];
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};
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void main ()
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{
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float thisLaneData = inputDataArray [gl_LocalInvocationID.x];
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bool laneActive = (thisLaneData > 0);
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uvec4 activeSlots = bitCount(uvec4(unpackUint2x32(gl_SubGroupLtMaskARB), uvec2(0)) & uvec4(unpackUint2x32(ballotARB (laneActive)), uvec2(0)));
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uint thisLaneOutputSlot = activeSlots.x + activeSlots.y;
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int firstInvocation = readFirstInvocationARB(1);
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int invocation = readInvocationARB(1, 0);
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if (laneActive) {
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outputDataArray[thisLaneOutputSlot] = thisLaneData;
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}
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}
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