49 lines
1.3 KiB
GLSL
49 lines
1.3 KiB
GLSL
// Copyright 2017 Mark Callow
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// SPDX-License-Identifier: Apache-2.0
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#version 450
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#extension GL_ARB_separate_shader_objects : enable
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#extension GL_ARB_shading_language_420pack : enable
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layout (location = 0) in vec4 inPos;
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layout (location = 1) in vec2 inUV;
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struct Instance
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{
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mat4 model;
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};
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// Keep the default value small to avoid MoltenVK issue 1420.
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// https://github.com/KhronosGroup/MoltenVK/issues/1420
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//layout(constant_id = 1) const int instanceCount = 1;
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// Sadly the above does not work on iOS, only macOS so declare
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// roughly the max size expected and in the app allocate the size
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// as declared.
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layout(constant_id = 1) const int instanceCount = 30;
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layout (binding = 0, std140) uniform UBO
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{
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mat4 projection;
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mat4 view;
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Instance instance[instanceCount];
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} ubo;
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// Workaround MoltenVK issue 1421 by passing instanceCount as a push constant.
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// https://github.com/KhronosGroup/MoltenVK/issues/1421.
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layout(push_constant) uniform PushConstants
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{
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uint instanceCount;
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} constants;
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layout (location = 0) out vec3 outUVW;
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void main()
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{
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float divisor = max(1.0, constants.instanceCount - 1);
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//float divisor = max(1.0, instanceCount - 1);
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outUVW = vec3(inUV, gl_InstanceIndex / divisor);
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mat4 modelView = ubo.view * ubo.instance[gl_InstanceIndex].model;
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gl_Position = ubo.projection * modelView * inPos;
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}
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