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use super::*;
pub struct Mesh {
_vertex_count: i32,
index_count: i32,
ibo: GLuint,
vao: GLuint,
}
impl Mesh {
pub fn draw(&self) {
unsafe{
gl::BindVertexArray(self.vao);
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER,self.ibo);
gl::DrawElements(gl::TRIANGLES, self.index_count, gl::UNSIGNED_INT, std::ptr::null());
}
}
}
#[derive(Default)]
pub struct MeshBuilder {
indices: Option<Vec<i32>>,
vertices: Option<Vec<f32>>,
}
impl MeshBuilder {
pub fn new() -> MeshBuilder {
MeshBuilder::default()
}
pub fn with_vertex_data(&mut self, vertex_data: &[f32]) -> &mut Self {
self.vertices = Some(vertex_data.to_vec());
self
}
pub fn with_index_data(&mut self, index_data: &[i32]) -> &mut Self {
self.indices = Some(index_data.to_vec());
self
}
pub fn build(&self) -> Mesh {
let (mut ibo, mut vao) = (0, 0);
let (mut vert_count, mut ind_count) = (0,0);
if let Some(ref data) = self.indices {
vert_count = data.len();
unsafe {
gl::GenBuffers(1, &mut ibo);
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, ibo);
gl::BufferData(
gl::ELEMENT_ARRAY_BUFFER,
(data.len() * std::mem::size_of::<GLint>()) as GLsizeiptr,
&data[0] as *const GLint as *const std::os::raw::c_void,
gl::STATIC_DRAW,
);
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 0);
}
}
if let Some(ref data) = self.vertices {
ind_count = data.len();
vao = 0;
let mut vbo = 0;
unsafe {
gl::GenVertexArrays(1, &mut vao);
gl::BindVertexArray(vao);
gl::GenBuffers(1, &mut vbo);
gl::BindBuffer(gl::ARRAY_BUFFER, vbo);
gl::BufferData(
gl::ARRAY_BUFFER,
(data.len() * std::mem::size_of::<GLfloat>()) as GLsizeiptr,
&data[0] as *const f32 as *const std::os::raw::c_void,
gl::STATIC_DRAW,
);
gl::BindVertexArray(vao);
gl::BindBuffer(gl::ARRAY_BUFFER, vbo);
let stride = 8 * std::mem::size_of::<GLfloat>() as GLsizei;
gl::EnableVertexAttribArray(0);
gl::EnableVertexAttribArray(1);
gl::EnableVertexAttribArray(2);
gl::VertexAttribPointer(0, 3, gl::FLOAT, gl::FALSE, stride, std::ptr::null());
gl::VertexAttribPointer(
1,
2,
gl::FLOAT,
gl::FALSE,
stride,
(3 * std::mem::size_of::<GLfloat>()) as *const std::os::raw::c_void,
);
gl::VertexAttribPointer(
2,
3,
gl::FLOAT,
gl::FALSE,
stride,
(5 * std::mem::size_of::<GLfloat>()) as *const std::os::raw::c_void,
);
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
gl::BindVertexArray(0);
}
}
Mesh{
_vertex_count: vert_count as i32,
index_count: ind_count as i32,
ibo,
vao,
}
}
}