Initial commit (new winit)

1 files changed, 118 insertions, 0 deletions

diff --git a/src/mesh.rs b/src/mesh.rs
new file mode 100644
index 0000000..2f54903
--- /dev/null
+++ b/src/mesh.rs
@@ -0,0 +1,118 @@
+use std::io::BufRead;
+
+use glow::HasContext;
+
+use crate::context;
+
+pub const ATTRIB_VERTEX: u32 = 0;
+pub const ATTRIB_NORMAL: u32 = 1;
+pub const ATTRIB_TEXCOORD: u32 = 2;
+
+pub struct Mesh {
+    pub vao: glow::VertexArray,
+    pub index_count: usize,
+}
+
+impl Mesh {
+    pub fn build(
+        ctx: &context::Context,
+        vertices: &Vec<f32>,
+        indices: &Vec<u32>,
+        snormals: &Option<Vec<f32>>,
+        stexcoords: &Option<Vec<f32>>,
+    ) -> Self {
+        unsafe {
+            let vao = ctx.gl.create_vertex_array().expect("failed to initialize vao");
+            ctx.gl.bind_vertex_array(Some(vao));
+
+            let vertices_vbo = ctx.gl.create_buffer().expect("failed to initialize vbo");
+            ctx.gl.bind_buffer(glow::ARRAY_BUFFER, Some(vertices_vbo));
+            ctx.gl.buffer_data_u8_slice(
+                glow::ARRAY_BUFFER,
+                std::slice::from_raw_parts(
+                    vertices.as_ptr() as _,
+                    vertices.len() * std::mem::size_of::<f32>(),
+                ),
+                glow::STATIC_DRAW,
+            );
+            ctx.gl.vertex_attrib_pointer_f32(ATTRIB_VERTEX, 3, glow::FLOAT, false, 0, 0);
+            ctx.gl.enable_vertex_attrib_array(ATTRIB_VERTEX);
+
+            let indices_vbo = ctx.gl.create_buffer().expect("failed to initialize vbo");
+            ctx.gl.bind_buffer(glow::ELEMENT_ARRAY_BUFFER, Some(indices_vbo));
+            ctx.gl.buffer_data_u8_slice(
+                glow::ELEMENT_ARRAY_BUFFER,
+                std::slice::from_raw_parts(
+                    indices.as_ptr() as _,
+                    indices.len() * std::mem::size_of::<f32>(),
+                ),
+                glow::STATIC_DRAW,
+            );
+
+            if let Some(normals) = snormals {
+                let normals_vbo = ctx.gl.create_buffer().expect("failed to initialize vbo");
+                ctx.gl.bind_buffer(glow::ARRAY_BUFFER, Some(normals_vbo));
+                ctx.gl.buffer_data_u8_slice(
+                    glow::ARRAY_BUFFER,
+                    std::slice::from_raw_parts(
+                        normals.as_ptr() as _,
+                        normals.len() * std::mem::size_of::<f32>(),
+                    ),
+                    glow::STATIC_DRAW,
+                );
+                ctx.gl.vertex_attrib_pointer_f32(ATTRIB_NORMAL, 3, glow::FLOAT, false, 0, 0);
+                ctx.gl.enable_vertex_attrib_array(ATTRIB_NORMAL);
+            }
+
+            if let Some(texcoords) = stexcoords {
+                let texcoords_vbo = ctx.gl.create_buffer().expect("failed to initialize vbo");
+                ctx.gl.bind_buffer(glow::ARRAY_BUFFER, Some(texcoords_vbo));
+                ctx.gl.buffer_data_u8_slice(
+                    glow::ARRAY_BUFFER,
+                    std::slice::from_raw_parts(
+                        texcoords.as_ptr() as _,
+                        texcoords.len() * std::mem::size_of::<f32>(),
+                    ),
+                    glow::STATIC_DRAW,
+                );
+                ctx.gl.vertex_attrib_pointer_f32(ATTRIB_TEXCOORD, 2, glow::FLOAT, false, 0, 0);
+                ctx.gl.enable_vertex_attrib_array(ATTRIB_TEXCOORD);
+            }
+
+            Self {
+                vao,
+                index_count: indices.len(),
+            }
+        }
+    }
+
+    pub fn new(ctx: &context::Context, mut bytes: &[u8]) -> Self {
+        let lopts = tobj::LoadOptions {
+            triangulate: true,
+            single_index: true,
+            ..Default::default()
+        };
+        let (meshes, _materials) = tobj::load_obj_buf(
+            &mut bytes,
+            &lopts,
+            |_| Err(tobj::LoadError::GenericFailure)
+        ).expect("failed to load mesh");
+        let mesh = meshes.into_iter().next()
+            .expect("failed to load mesh")
+            .mesh;
+        Self::build(
+            ctx,
+            &mesh.positions,
+            &mesh.indices,
+            &Some(mesh.normals),
+            &Some(mesh.texcoords),
+        )
+    }
+
+    pub fn render(&self, ctx: &context::Context) {
+        unsafe {
+            ctx.gl.bind_vertex_array(Some(self.vao));
+            ctx.gl.draw_elements(glow::TRIANGLES, self.index_count as _, glow::UNSIGNED_INT, 0);
+        }
+    }
+}