Lighting

说明

内容

• Rendering a geometry with a vertex diffuse lighting
• Rendering a geometry with a fragment specular lighting
• Rendering a normal mapped geometry
• Drawing a reflective and refractive geometry using cubemaps
• Adding shadows to the scene

介绍

…

Rendering a geometry with a vertex diffuse lighting

vertex

#version 450
layout( location = 0 ) in vec4 app_position;
layout( location = 1 ) in vec3 app_normal;
layout( set = 0, binding = 0 ) uniform UniformBuffer {
    mat4 ModelViewMatrix;
    mat4 ProjectionMatrix;
};
layout( location = 0 ) out float vert_color;
void main() {
    gl_Position = ProjectionMatrix * ModelViewMatrix *
        app_position;
    vec3 normal = mat3( ModelViewMatrix ) * app_normal;
    vert_color = max( 0.0, dot( normal, vec3( 0.58, 0.58, 0.58 ) )
                    ) + 0.1;
}

fragment

#version 450
layout( location = 0 ) in float vert_color;
layout( location = 0 ) out vec4 frag_color;
void main() {
    frag_color = vec4( vert_color );
}

…

Rendering a geometry with a fragment specular lighting

#version 450
layout( location = 0 ) in vec3 vert_position;
layout( location = 1 ) in vec3 vert_normal;
layout( push_constant ) uniform LightParameters {
    vec4 Position;
} Light;
layout( location = 0 ) out vec4 frag_color;
void main() {
    vec3 normal_vector = normalize( vert_normal );
    vec3 light_vector = normalize( Light.Position.xyz -
                                  vert_position );
    float diffuse_term = max( 0.0, dot( normal_vector, light_vector
                                      ) );
    frag_color = vec4( diffuse_term + 0.1 );
    if( diffuse_term > 0.0 ) {
        vec3 view_vector = normalize( vec3( 0.0, 0.0, 0.0 ) -
                                     vert_position.xyz );
        vec3 half_vector = normalize( view_vector + light_vector );
        float shinniness = 60.0;
        float specular_term = pow( dot( half_vector, normal_vector ),
                                  shinniness );
        frag_color += vec4( specular_term );
    }
}

normal mapeed geometry

vertex

#version 450
layout( location = 0 ) in vec4 app_position;
layout( location = 1 ) in vec3 app_normal;
layout( location = 2 ) in vec2 app_texcoord;
layout( location = 3 ) in vec3 app_tangent;
layout( location = 4 ) in vec3 app_bitangent;
layout( set = 0, binding = 0 ) uniform UniformBuffer {
    mat4 ModelViewMatrix;
    mat4 ProjectionMatrix;
};
layout( location = 0 ) out vec3 vert_position;
layout( location = 1 ) out vec2 vert_texcoord;
layout( location = 2 ) out vec3 vert_normal;
layout( location = 3 ) out vec3 vert_tanget;
layout( location = 4 ) out vec3 vert_bitanget;
void main() {
    vec4 position = ModelViewMatrix * app_position;
    gl_Position = ProjectionMatrix * position;
    vert_position = position.xyz;
    vert_texcoord = app_texcoord;
    vert_normal = mat3( ModelViewMatrix ) * app_normal;
    vert_tanget = mat3( ModelViewMatrix ) * app_tangent;
    vert_bitanget = mat3( ModelViewMatrix ) * app_bitangent;
}

fragment

#version 450
layout( location = 0 ) in vec3 vert_position;
layout( location = 1 ) in vec2 vert_texcoord;
layout( location = 2 ) in vec3 vert_normal;
layout( location = 3 ) in vec3 vert_tanget;
layout( location = 4 ) in vec3 vert_bitanget;
layout( set = 0, binding = 1 ) uniform sampler2D ImageSampler;
layout( push_constant ) uniform LightParameters {
    vec4 Position;
} Light;
layout( location = 0 ) out vec4 frag_color;
void main() {
    vec3 normal = 2 * texture( ImageSampler, vert_texcoord ).rgb -
        1.0;
    vec3 normal_vector = normalize( mat3( vert_tanget,
                                         vert_bitanget, vert_normal) * normal );
    vec3 light_vector = normalize( Light.Position.xyz -
                                  vert_position );
    float diffuse_term = max( 0.0, dot( normal_vector, light_vector
                                      ) ) * max( 0.0, dot( vert_normal, light_vector ) );
    frag_color = vec4( diffuse_term + 0.1 );
    if( diffuse_term > 0.0 ) {
        vec3 half_vector = normalize(normalize( -vert_position.xyz )
                                     + light_vector);
        float specular_term = pow( dot( half_vector, normal_vector ),
                                  60.0 );
        frag_color += vec4( specular_term );
    }
}

Drawing a reflective and refractive geometry using cubemaps

order:+X,-X,+Y,-Y,+Z,-Z

vertex

#version 450
layout( location = 0 ) in vec4 app_position;
layout( location = 1 ) in vec3 app_normal;
layout( set = 0, binding = 0 ) uniform UniformBuffer {
    mat4 ModelViewMatrix;
    mat4 ProjectionMatrix;
};
layout( location = 0 ) out vec3 vert_position;
layout( location = 1 ) out vec3 vert_normal;
void main() {
    vert_position = app_position.xyz;
    vert_normal = app_normal;
    gl_Position = ProjectionMatrix * ModelViewMatrix *
        app_position;
}

fragment

#version 450
layout( location = 0 ) in vec3 vert_position;
layout( location = 1 ) in vec3 vert_normal;
layout( set = 0, binding = 1 ) uniform samplerCube Cubemap;
layout( push_constant ) uniform LightParameters {
    vec4 Position;
} Camera;
layout( location = 0 ) out vec4 frag_color;
void main() {
    vec3 view_vector = vert_position - Camera.Position.xyz;
    float angle = smoothstep( 0.3, 0.7, dot( normalize( -
                                                       view_vector ), vert_normal ) );
    vec3 reflect_vector = reflect( view_vector, vert_normal );
    vec4 reflect_color = texture( Cubemap, reflect_vector );
    vec3 refrac_vector = refract( view_vector, vert_normal, 0.3 );
    vec4 refract_color = texture( Cubemap, refrac_vector );
    frag_color = mix( reflect_color, refract_color, angle );
}

add shadow to the scene