#version 450
#extension GL_ARB_separate_shader_objects : enable

layout(push_constant) uniform PushConstants {
    mat4 model;
} push;

layout(binding = 0) uniform ObjectUniformData {
    mat4 view;
    mat4 projection;
    float time;
    vec3 light_position;
    vec3 light_directional_rotation;
    vec3 camera_position;
} ubo;

layout(location = 0) in vec3 position;
layout(location = 1) in vec2 uv;
layout(location = 2) in vec3 normal;
layout(location = 3) in vec4 tangent;
layout(location = 4) in ivec4 bone_index;
layout(location = 5) in vec4 bone_weight;

layout(location = 0) out vec2 tex_coords;
layout(location = 1) out vec3 normal_wld;
layout(location = 2) out vec3 position_wld;
layout(location = 3) out mat3 tbn;

out gl_PerVertex {
    vec4 gl_Position;
};

void main() {
    // Vertex position
    gl_Position = ubo.projection * ubo.view * push.model * vec4(position, 1.0);
    position_wld = vec3(push.model * vec4(position, 1.0));

    // Just interpolate UV coords, no transformation needed
    tex_coords = uv;

    // This should probably be in object space? idk
    normal_wld = vec3(mat3(transpose(inverse(push.model))) * normal);

    // Tangent->object space matrix
    vec3 tangent3 = vec3(tangent.xy, 1.0);
    vec3 bitangent = -cross(tangent3, normal_wld);
    vec3 t = normalize(vec3(push.model * vec4(tangent3, 0.0)));
    vec3 b = normalize(vec3(push.model * vec4(bitangent, 0.0)));
    vec3 n = normalize(vec3(push.model * vec4(normal_wld, 0.0)));
    tbn = mat3(t, b, n);
}