1 files changed, 76 insertions, 3 deletions
diff --git a/engine/src/renderer/mod.rs b/engine/src/renderer/mod.rs
index 9cd379d..3c42f93 100644
--- a/engine/src/renderer/mod.rs
+++ b/engine/src/renderer/mod.rs
@@ -1,10 +1,17 @@
-use std::ffi::{c_void, CString};
+use std::ffi::{c_float, c_void, CString};
+use std::mem::size_of;
 use std::process::abort;
+use std::ptr::null;
 
 use glfw::WindowSize;
 
+use crate::renderer::vertex_array::{PrimitiveKind, VertexArray};
+use crate::renderer::vertex_buffers::{BufferUsage, VertexBuffers};
 use crate::vector::Vec2;
 
+mod vertex_array;
+mod vertex_buffers;
+
 pub fn initialize(window: &glfw::Window) -> Result<(), Error>
 {
     gl::load_with(|symbol| {
@@ -30,10 +37,51 @@ pub fn initialize(window: &glfw::Window) -> Result<(), Error>
     Ok(())
 }
 
-pub fn render()
+pub fn render<'renderable>(renderables: impl IntoIterator<Item = &'renderable Renderable>)
 {
     unsafe {
-        gl::Clear(gl::COLOR_BUFFER_BIT | gl::DEPTH_BUFFER_BIT);
+        gl::Clear(gl::COLOR_BUFFER_BIT);
+    }
+
+    for renderable in renderables {
+        renderable.shader_program.activate();
+
+        renderable.vertex_arr.draw(PrimitiveKind::Triangles, 0, 3);
+    }
+}
+
+pub struct Renderable
+{
+    shader_program: crate::shader::Program,
+    vertex_arr: VertexArray,
+}
+
+impl Renderable
+{
+    pub fn new(shader_program: crate::shader::Program, vertices: &[f32]) -> Self
+    {
+        let vertex_arr = VertexArray::new();
+
+        vertex_arr.bind();
+
+        let vertex_buffer = VertexBuffers::<1>::new();
+
+        vertex_buffer
+            .store(0, vertices, BufferUsage::Static)
+            .unwrap();
+
+        vertex_attrib_ptr(0);
+        enable_vertex_attrib_array(0);
+
+        unsafe {
+            gl::BindBuffer(gl::ARRAY_BUFFER, 0);
+            gl::BindVertexArray(0);
+        }
+
+        Self {
+            shader_program,
+            vertex_arr,
+        }
     }
 }
 
@@ -57,3 +105,28 @@ pub enum Error
     #[error("Failed to get window size")]
     GetWindowSizeFailed(#[source] glfw::Error),
 }
+
+fn vertex_attrib_ptr(index: usize)
+{
+    let stride = 3 * size_of::<c_float>();
+
+    unsafe {
+        #[allow(clippy::cast_possible_wrap, clippy::cast_possible_truncation)]
+        gl::VertexAttribPointer(
+            index as gl::types::GLuint,
+            3,
+            gl::FLOAT,
+            gl::FALSE,
+            stride as gl::types::GLsizei,
+            null(),
+        );
+    }
+}
+
+fn enable_vertex_attrib_array(index: usize)
+{
+    unsafe {
+        #[allow(clippy::cast_possible_truncation)]
+        gl::EnableVertexAttribArray(index as gl::types::GLuint);
+    }
+}