// Copyright 2016 Mark Callow
// SPDX-License-Identifier: Apache-2.0
 
// Vertex shader for cube sample.
 
#version 450

#extension GL_ARB_separate_shader_objects : enable
#extension GL_ARB_shading_language_420pack : enable

#if 0
layout (location = 0) in vec3 inPos;
layout (location = 1) in vec3 inNormal;
layout (location = 2) in vec2 inUV;
layout (location = 3) in vec4 inColor;

layout (binding = 0) uniform UBO 
{
	mat4 projection;
	mat4 model;
	vec4 viewPos;
	float lodBias;
} ubo;

layout (location = 0) out vec2 outUV;
layout (location = 1) out vec4 outColor;
//layout (location = 1) out float outLodBias;
//layout (location = 2) out vec3 outNormal;
//layout (location = 3) out vec3 outViewVec;
//layout (location = 4) out vec3 outLightVec;

out gl_PerVertex 
{
    vec4 gl_Position;   
};

void main() 
{
	outUV = inUV;
	outColor = inColor;
	//outLodBias = ubo.lodBias;

	//vec3 worldPos = vec3(ubo.model * vec4(inPos, 1.0));

	gl_Position = ubo.projection * ubo.model * vec4(inPos.xyz, 1.0);

#if 0
    vec4 pos = ubo.model * vec4(inPos, 1.0);
	outNormal = mat3(inverse(transpose(ubo.model))) * inNormal;
	vec3 lightPos = vec3(0.0);
	vec3 lPos = mat3(ubo.model) * lightPos.xyz;
    outLightVec = lPos - pos.xyz;
    outViewVec = ubo.viewPos.xyz - pos.xyz;	
#endif	

   // GL->VK conventions. Sigh!
   //gl_Position.y = -gl_Position.y;
   //gl_Position.z = (gl_Position.z + gl_Position.w) / 2.0;
}
#endif

#if 0
layout (location = 0) in vec3 inPos;
layout (location = 1) in vec2 inUV;
layout (location = 2) in vec3 inNormal;

layout (binding = 0) uniform UBO 
{
	mat4 projection;
	mat4 model;
	vec4 viewPos;
	float lodBias;
} ubo;

layout (location = 0) out vec2 outUV;
layout (location = 1) out float outLodBias;
layout (location = 2) out vec3 outNormal;
layout (location = 3) out vec3 outViewVec;
layout (location = 4) out vec3 outLightVec;

out gl_PerVertex 
{
    vec4 gl_Position;   
};

void main() 
{
	outUV = inUV;
	outLodBias = ubo.lodBias;

	vec3 worldPos = vec3(ubo.model * vec4(inPos, 1.0));

	gl_Position = ubo.projection * ubo.model * vec4(inPos.xyz, 1.0);

    vec4 pos = ubo.model * vec4(inPos, 1.0);
	outNormal = mat3(inverse(transpose(ubo.model))) * inNormal;
	vec3 lightPos = vec3(0.0);
	vec3 lPos = mat3(ubo.model) * lightPos.xyz;
    outLightVec = lPos - pos.xyz;
    outViewVec = ubo.viewPos.xyz - pos.xyz;		
}
#endif

    layout (location = 0) in vec3 inPos;
//    layout (location = 3) in vec4 inColor;
//    layout (location = 0) out vec4 outColor;

layout (std140, binding = 0) uniform UBO 
{
	mat4 projection;
	mat4 model;
	mat4 view;
	vec4 viewPos;
	float lodBias;
} ubo;

void main() {
   //outColor = inColor;r
   mat4 mvp = ubo.projection * ubo.view * ubo.model;
   gl_Position = mvp * vec4(inPos, 1.0);
   //gl_Position = vec4(inPos * 0.5, 1.0);
   //gl_PointSize = 2.0;
}