Struct thin_engine::prelude::Program

pub struct Program { /* private fields */ }

A combination of shaders linked together.

Implementations

impl Program

pub fn new<'a, F, I>( facade: &F, input: I, ) -> Result<Program, ProgramCreationError>

where I: Into<ProgramCreationInput<'a>>, F: Facade + ?Sized,

Builds a new program.

pub fn from_source<'a, F>( facade: &F, vertex_shader: &'a str, fragment_shader: &'a str, geometry_shader: Option<&'a str>, ) -> Result<Program, ProgramCreationError>

where F: Facade + ?Sized,

Builds a new program from GLSL source code.

A program is a group of shaders linked together.

Parameters

• vertex_shader: Source code of the vertex shader.
• fragment_shader: Source code of the fragment shader.
• geometry_shader: Source code of the geometry shader.

Example

let program = glium::Program::from_source(&display, vertex_source, fragment_source,
    Some(geometry_source));

Examples found in repository

examples/simple.rs (lines 37-49)

fn main() {
    use Action::*;
    let (event_loop, window, display) = thin_engine::set_up().unwrap();
    window.set_title("Walk Test");
    let _ = window.set_cursor_grab(CursorGrabMode::Locked);
    window.set_cursor_visible(false);

    let mut input = InputMap::new([
        (vec![Input::keycode(KeyCode::Space)], Jump),
        (vec![Input::keycode(KeyCode::ArrowLeft), Input::keycode(KeyCode::KeyA)], Left),
        (vec![Input::keycode(KeyCode::ArrowRight), Input::keycode(KeyCode::KeyD)], Right),
        (vec![Input::keycode(KeyCode::ArrowUp), Input::keycode(KeyCode::KeyW)], Forward),
        (vec![Input::keycode(KeyCode::ArrowDown), Input::keycode(KeyCode::KeyS)], Back)
    ]);

    let (indices, verts, norms) = mesh!(
        &display, &teapot::INDICES, &teapot::VERTICES, &teapot::NORMALS
    );
    let draw_parameters = DrawParameters {
        backface_culling: draw_parameters::BackfaceCullingMode::CullClockwise,
        ..params::alias_3d()
    };
    let program = Program::from_source(
        &display, shaders::VERTEX,
        "#version 140
        out vec4 colour;
        in vec3 v_normal;
        uniform vec3 light;

        const vec3 albedo = vec3(0.1, 1.0, 0.3);
        void main(){
            float light_level = dot(light, v_normal);
            colour = vec4(albedo * light_level, 1.0);
        }", None,
    ).unwrap();

    let mut pos = vec3(0.0, 0.0, -30.0);
    let mut rot = vec2(0.0, 0.0);
    let mut gravity = 0.0;

    const DELTA: f32 = 0.016;

    thin_engine::run(event_loop, &mut input, |input| {
        display.resize(window.inner_size().into());
        let mut frame = display.draw();
        let view = Mat4::view_matrix_3d(frame.get_dimensions(), 1.0, 1024.0, 0.1);

        //handle gravity and jump
        gravity += DELTA * 9.5;
        if input.pressed(Jump) {
            gravity = -10.0;
        }

        //set camera rotation
        rot += input.mouse_move.scale(DELTA * 2.0);
        rot.y = rot.y.clamp(-PI / 2.0, PI / 2.0);
        let rx = Quaternion::from_y_rotation(rot.x);
        let ry = Quaternion::from_x_rotation(rot.y);
        let rot = rx * ry;

        //move player based on view and gravity
        let x = input.axis(Right, Left);
        let y = input.axis(Forward, Back);
        let move_dir = vec3(x, 0.0, y).normalise();
        pos += move_dir.transform(&Mat3::from_rot(rx)).scale(5.0 * DELTA);
        pos.y = (pos.y - gravity * DELTA).max(0.0);

        frame.clear_color_and_depth((0.0, 0.0, 0.0, 1.0), 1.0);
        //draw teapot
        frame.draw(
            (&verts, &norms), &indices,
            &program, &uniform! {
                view: view,
                model: Mat4::from_scale(Vec3::splat(0.1)),
                camera: Mat4::from_inverse_transform(pos, Vec3::ONE, rot),
                light: vec3(1.0, -0.9, -1.0).normalise()
            },
            &draw_parameters,
        ).unwrap();

        frame.finish().unwrap();
        thread::sleep(Duration::from_millis(16));
    }).unwrap();
}

examples/simple-fxaa.rs (lines 51-68)

fn main() {
    use Action::*;
    let (event_loop, window, display) = thin_engine::set_up().unwrap();
    window.set_title("FXAA Test");
    let _ = window.set_cursor_grab(CursorGrabMode::Locked);
    window.set_cursor_visible(false);

    let mut colour = ResizableTexture2D::default();
    let mut depth = ResizableDepthTexture2D::default();

    let mut input = InputMap::new([
        (vec![Input::keycode(KeyCode::ArrowLeft), Input::keycode(KeyCode::KeyA)], Left),
        (vec![Input::keycode(KeyCode::ArrowRight), Input::keycode(KeyCode::KeyD)], Right),
        (vec![Input::keycode(KeyCode::ArrowUp), Input::keycode(KeyCode::KeyW)], Forward),
        (vec![Input::keycode(KeyCode::ArrowDown), Input::keycode(KeyCode::KeyS)], Back),
        (vec![Input::keycode(KeyCode::KeyF)], FXAA),
        (vec![Input::keycode(KeyCode::Space)], Jump)
    ]);
    let (screen_indices, verts, uvs) = mesh!(
        &display, &screen::INDICES, &screen::VERTICES, &screen::UVS
    );
    let screen_mesh = (&verts, &uvs);
    let (indices, verts, norms) = mesh!(
        &display, &teapot::INDICES, &teapot::VERTICES, &teapot::NORMALS
    );
    let teapot_mesh = (&verts, &norms);
    let draw_parameters = DrawParameters {
        backface_culling: draw_parameters::BackfaceCullingMode::CullClockwise,
        ..params::alias_3d()
    };
    let mut fxaa_on = true;
    let program = Program::from_source(
        &display, shaders::VERTEX,
        "#version 140
        out vec4 colour;
        in vec3 v_normal;
        uniform vec3 light;
        uniform mat4 camera;
        uniform vec3 ambient;
        uniform vec3 albedo;
        uniform float shine;
        void main() {
            vec3 camera_dir = inverse(mat3(camera)) * vec3(0, 0, -1);
            vec3 half_dir = normalize(camera_dir + light);
            float specular = pow(max(dot(half_dir, v_normal), 0.0), shine);
            float light_level = max(dot(light, v_normal), 0.0);
            colour = vec4(albedo * light_level + ambient + vec3(specular), 1.0);
        }", None
    ).unwrap();
    let fxaa = shaders::fxaa_shader(&display).unwrap();
    let normal = Program::from_source(
        &display, shaders::SCREEN_VERTEX, 
        "#version 140
        in vec2 uv;
        uniform sampler2D tex;
        out vec4 colour;
        void main() {
            colour = texture(tex, uv);
        }", None
    ).unwrap();

    let mut pos = vec3(0.0, 0.0, -30.0);
    let mut rot = vec2(0.0, 0.0);
    const DELTA: f32 = 0.016;

    thin_engine::run(event_loop, &mut input, |input| {
        // using a small resolution to show the effect.
        // `let size = window.inner_size().into();` 
        // can be used isntead to set resolution to window size
        let size = (380, 216);
        display.resize(size);
        depth.resize_to_display(&display);
        colour.resize_to_display(&display);

        //press f to toggle FXAA
        if input.pressed(FXAA) { fxaa_on = !fxaa_on }

        let colour = colour.texture.as_ref().unwrap();
        let depth = depth.texture.as_ref().unwrap();
        let mut frame = SimpleFrameBuffer::with_depth_buffer(
            &display, colour, depth
        ).unwrap();

        let view = Mat4::view_matrix_3d(size, 1.0, 1024.0, 0.1);        
        //set camera rotation
        rot += input.mouse_move.scale(DELTA * 2.0);
        rot.y = rot.y.clamp(-PI / 2.0, PI / 2.0);
        let rx = Quaternion::from_y_rotation(rot.x);
        let ry = Quaternion::from_x_rotation(rot.y);
        let rot = rx * ry;

        //move player based on view
        let x = input.axis(Right, Left);
        let y = input.axis(Forward, Back);
        let move_dir = vec3(x, 0.0, y).normalise().scale(5.0*DELTA);
        pos += move_dir.transform(&Mat3::from_rot(rx));

        frame.clear_color_and_depth((0.0, 0.0, 0.0, 1.0), 1.0);
        //draw teapot
        frame.draw(
            teapot_mesh, &indices,
            &program, &uniform! {
                view: view,
                model: Mat4::from_scale(Vec3::splat(0.1)),
                camera: Mat4::from_inverse_transform(pos, Vec3::ONE, rot),
                light: vec3(0.1, 0.25, -1.0).normalise(),
                albedo: vec3(0.5, 0.1, 0.4),
                ambient: vec3(0.0, 0.05, 0.1),
                shine: 10.0f32,
            },
            &draw_parameters,
        ).unwrap();

        let mut frame = display.draw();
        frame.draw(
            screen_mesh, &screen_indices, if fxaa_on { &fxaa } else { &normal },
            &shaders::fxaa_uniforms(colour), &DrawParameters::default()
        ).unwrap();
        frame.finish().unwrap();
        thread::sleep(Duration::from_millis(16));
    }).unwrap();
}

pub fn get_binary(&self) -> Result<Binary, GetBinaryError>

Returns the program’s compiled binary.

You can store the result in a file, then reload it later. This avoids having to compile the source code every time.

pub fn get_frag_data_location(&self, name: &str) -> Option<u32>

Returns the location of an output fragment, if it exists.

The location is low-level information that is used internally by glium. You probably don’t need to call this function.

You can declare output fragments in your shaders by writing:

out vec4 foo;

pub fn get_uniform(&self, name: &str) -> Option<&Uniform>

Returns informations about a uniform variable, if it exists.

pub fn uniforms(&self) -> Iter<'_, String, Uniform>

Returns an iterator to the list of uniforms.

Example

for (name, uniform) in program.uniforms() {
    println!("Name: {} - Type: {:?}", name, uniform.ty);
}

pub fn get_uniform_blocks( &self, ) -> &HashMap<String, UniformBlock, BuildHasherDefault<FnvHasher>>

Returns a list of uniform blocks.

Example

for (name, uniform) in program.get_uniform_blocks() {
    println!("Name: {}", name);
}

pub fn get_transform_feedback_buffers(&self) -> &[TransformFeedbackBuffer]

Returns the list of transform feedback varyings.

pub fn transform_feedback_matches( &self, format: &&'static [(Cow<'static, str>, usize, i32, AttributeType, bool)], stride: usize, ) -> bool

True if the transform feedback output of this program matches the specified VertexFormat and stride.

The stride is the number of bytes between two vertices.

pub fn get_output_primitives(&self) -> Option<OutputPrimitives>

Returns the type of geometry that transform feedback would generate, or None if it depends on the vertex/index data passed when drawing.

This corresponds to GL_GEOMETRY_OUTPUT_TYPE or GL_TESS_GEN_MODE. If the program doesn’t contain either a geometry shader or a tessellation evaluation shader, returns None.

pub fn has_tessellation_shaders(&self) -> bool

Returns true if the program contains a tessellation stage.

pub fn has_tessellation_control_shader(&self) -> bool

Returns true if the program contains a tessellation control stage.

pub fn has_tessellation_evaluation_shader(&self) -> bool

Returns true if the program contains a tessellation evaluation stage.

pub fn has_geometry_shader(&self) -> bool

Returns true if the program contains a geometry shader.

pub fn get_attribute(&self, name: &str) -> Option<&Attribute>

Returns informations about an attribute, if it exists.

pub fn attributes(&self) -> Iter<'_, String, Attribute>

Returns an iterator to the list of attributes.

Example

for (name, attribute) in program.attributes() {
    println!("Name: {} - Type: {:?}", name, attribute.ty);
}

pub fn has_srgb_output(&self) -> bool

Returns true if the program has been configured to output sRGB instead of RGB.

pub fn get_shader_storage_blocks( &self, ) -> &HashMap<String, UniformBlock, BuildHasherDefault<FnvHasher>>

Returns the list of shader storage blocks.

Example

for (name, uniform) in program.get_shader_storage_blocks() {
    println!("Name: {}", name);
}

pub fn get_atomic_counters( &self, ) -> &HashMap<String, UniformBlock, BuildHasherDefault<FnvHasher>>

Returns the list of shader storage blocks.

Example

for (name, uniform) in program.get_atomic_counters() {
    println!("Name: {}", name);
}

pub fn get_subroutine_uniforms( &self, ) -> &HashMap<(String, ShaderStage), SubroutineUniform, BuildHasherDefault<FnvHasher>>

Returns the subroutine uniforms of this program.

Since subroutine uniforms are unique per shader and not per program, the keys of the HashMap are in the format ("subroutine_name", ShaderStage).

Example

for (&(ref name, shader), uniform) in program.get_subroutine_uniforms() {
    println!("Name: {}", name);
}

pub fn uses_point_size(&self) -> bool

Returns true if the program has been configured to use the gl_PointSize variable.

If the program uses gl_PointSize without having been configured appropriately, then setting the value of gl_PointSize will have no effect.

Trait Implementations

impl Debug for Program

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl GlObject for Program

type Id = Handle

The type of identifier for this object.

fn get_id(&self) -> Handle

Returns the id of the object.