// Copyright (C) 2020 Klaralvdalens Datakonsult AB (KDAB).
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

#version 450

layout(location = 0) in vec3 vertexPosition;
layout(location = 1) in vec3 vertexNormal;

layout(location = 0) out vec4 positionInLightSpace;
layout(location = 1) out vec3 position;
layout(location = 2) out vec3 normal;


layout(std140, binding = 0) uniform qt3d_render_view_uniforms {
  mat4 viewMatrix;
  mat4 projectionMatrix;
  mat4 viewProjectionMatrix;
  mat4 inverseViewMatrix;
  mat4 inverseProjectionMatrix;
  mat4 inverseViewProjectionMatrix;
  mat4 viewportMatrix;
  mat4 inverseViewportMatrix;
  vec4 textureTransformMatrix;
  vec3 eyePosition;
  float aspectRatio;
  float gamma;
  float exposure;
  float time;
};

layout(std140, binding = 1) uniform qt3d_command_uniforms {
  mat4 modelMatrix;
  mat4 inverseModelMatrix;
  mat4 modelView;
  mat3 modelNormalMatrix;
  mat4 inverseModelViewMatrix;
  mat4 mvp;
  mat4 inverseModelViewProjectionMatrix;
  mat3 modelViewNormal;
};

layout(std140, binding = 2) uniform qt3d_custom_uniforms {
 mat4 lightViewProjection;
 vec3 lightPosition;
 vec3 lightIntensity;

 vec3 ka;            // Ambient reflectivity
 vec3 kd;            // Diffuse reflectivity
 vec3 ks;            // Specular reflectivity
 float shininess;    // Specular shininess factor
};

void main()
{
    // positionInLightSpace = lightViewProjection * modelMatrix * vec4(vertexPosition, 1.0);
    const mat4 shadowMatrix = mat4(0.5, 0.0, 0.0, 0.0,
                                   0.0, 0.5, 0.0, 0.0,
                                   0.0, 0.0, 0.5, 0.0,
                                   0.5, 0.5, 0.5, 1.0);

    positionInLightSpace = shadowMatrix * lightViewProjection * modelMatrix * vec4(vertexPosition, 1.0);

    normal = normalize(modelViewNormal * vertexNormal);
    position = vec3(modelView * vec4(vertexPosition, 1.0));

    gl_Position = mvp * vec4(vertexPosition, 1.0);
}