Struct dzahui::simulation::shader::Shader

pub(crate) struct Shader {
    pub(crate) id: u32,
}

General information

A shader instance stores the id representing a combination of a vertex and fragment shader compiled (OpenGL Shading Language) and attached to an OpenGL program. Later on, an instance of such shader can be attached to an OpenGL context to use in conjunction with a series of vertices to draw to screen.

Fields

• id - An id field setup by OpenGL to uniquely identify shaders being passed.

Fields

id: u32

Implementations

impl Shader

pub fn new(
    vertex_path: impl AsRef<str>,
    fragment_path: impl AsRef<str>
) -> Result<Self, Error>

General information

Creates a new shader program composed of both a vertex and a fragment shader. Since it uses gl crate, it’s necessary that an openGL context has been initialized. Unsafe part stops rust from caching errors while compiling shaders, therefore print statements will be sent to the terminal containing a message in case an error has happened. Later use of faulty shaders will stop the program from running, but debbuging becomes hard since little information is provided by the gl crate. Should enable logging errors at a later date. Regarding the steps the function uses: first it opens and read files to strings. Then, shaders are casted to CStrings. After that, each shader is sent to be compiled and linked to a u32 variable. Finally, the u32 varaibles are linked to an OpenGL program with an id and cache is erased (compiled programs are already associated to a program, therefore can be safely erased). This last id is returned inside Shader structure.

Parameters

• vertex_path - Path to a vertex shader file.
• fragment_path - Path to a fragment shader file.

pub fn use_shader(&self)

Use a certain pair of shaders identified by id. Program can have multiple shaders at once, but only one can be used at a time.

pub fn set_mat4(
    &self,
    opengl_variable_name: &str,
    mat4_value: &Matrix4<f32>
) -> Result<(), Error>

Send a 4x4 matrix variable to vertex shader. Matrix variable has to be declared as a uniform in shader and it’s name must be known for this to work.

Trait Implementations

impl Debug for Shader

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

Formats the value using the given formatter.

impl PartialEq<Shader> for Shader

fn eq(&self, other: &Shader) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for Shader

impl StructuralEq for Shader

impl StructuralPartialEq for Shader