(fix): fixed GPU project matrix by #5; fixed perspect correct in line…

… draw

examples/sandbox.rs

@@ -90,13 +90,12 @@ fn main() {
     let mut renderer = create_renderer(WINDOW_WIDTH, WINDOW_HEIGHT, camera);
     renderer.set_front_face(FrontFace::CCW);
     renderer.set_face_cull(FaceCull::Back);
-    // renderer.enable_framework();
     let mut texture_storage = TextureStorage::default();
 
     // data prepare, from OBJ model
-    const MODEL_ROOT_DIR: &str = "./resources/Red";
+    const MODEL_ROOT_DIR: &str = "./resources/Son Goku";
     let (meshes, mtllibs) = model::load_from_file(
-        &format!("{}/{}", MODEL_ROOT_DIR, "Red.obj"),
+        &format!("{}/{}", MODEL_ROOT_DIR, "Goku.obj"),
         model::PreOperation::None,
     )
     .unwrap();
@@ -157,14 +156,17 @@ fn main() {
             if event_key_down(Key::from_char('e')) {
                 camera.move_offset(math::Vec3::new(0.0, -0.01, 0.0));
             }
+            if event_key_down(Key::from_char('t')) {
+                renderer.toggle_framework();
+            }
         }
 
         // render
         renderer.clear(&math::Vec4::new(0.2, 0.2, 0.2, 1.0));
         renderer.clear_depth();
 
         let model = math::create_translate(&math::Vec3::new(0.0, 0.0, -4.0))
-            * math::create_eular_rotate_y(rotation.to_radians());
+            * math::create_eular_rotate_x(rotation.to_radians());
 
         for data in &vertex_datas {
             // set data into uniform

src/camera.rs

@@ -35,7 +35,7 @@ impl Frustum {
                 math::Mat4::from_row(&[
                     near / half_w,           0.0,                       0.0,                             0.0,
                               0.0, near / half_h,                       0.0,                             0.0,
-                              0.0,           0.0, far + near / (near - far), 2.0 * far * near / (near - far),
+                              0.0,           0.0,(far + near) / (near - far), 2.0 * far * near / (near - far),
                               0.0,           0.0,                      -1.0,                             0.0,
                 ])
             },

src/cpu_renderer.rs

@@ -122,6 +122,10 @@ impl renderer::RendererInterface for Renderer {
     fn disable_framework(&mut self) {
         self.enable_framework = false;
     }
+
+    fn toggle_framework(&mut self) {
+        self.enable_framework = !self.enable_framework;
+    }
 }
 
 impl Renderer {
@@ -228,11 +232,12 @@ impl Renderer {
             for i in 0..3 {
                 let mut v1 = vertices[i];
                 let mut v2 = vertices[(i + 1) % 3];
-                v1.position.z = 1.0 / v1.position.z;
-                v2.position.z = 1.0 / v2.position.z;
+
+                shader::vertex_rhw_init(&mut v1);
+                shader::vertex_rhw_init(&mut v2);
 
                 rasterize_line(
-                    &Line::new(v1, v2),
+                    &mut Line::new(v1, v2),
                     &self.shader.pixel_shading,
                     &self.uniforms,
                     texture_storage,

src/gpu_renderer.rs

@@ -4,7 +4,7 @@ use crate::{
     line::Line,
     math::{self, Berycentric},
     renderer::*,
-    shader::*,
+    shader::{*, self},
     texture::TextureStorage,
 };
 
@@ -74,9 +74,9 @@ impl RendererInterface for Renderer {
             }
 
             // set truely z
-            /* NOTIC: in OpenGL, after MVP transform, z in [-1, 1], then OpenGL do `z = (z + 1) / 2` to make z in [0, 1],
+            /* NOTIC: in OpenGL, after MVP & Perspective divide, z in [-1, 1], then OpenGL do `z = (z + 1) / 2` to make z in [0, 1],
                 then, use `1 / z` to test depth.
-                But here we replace transformed z to it's original z which transformed after MV.
+                But here we replace transformed z to it's original z which transformed after MVP.
                 Traditionally we will save `-1.0 / v.position.w` into v.rhw and use it interpolate attributes.
                 But here I don't do it(because I'm lazy :D, maybe do it later).
             */
@@ -88,6 +88,7 @@ impl RendererInterface for Renderer {
             for v in &mut vertices {
                 v.position.x /= v.position.w;
                 v.position.y /= v.position.w;
+                v.position.w = 1.0;
             }
 
             // Viewport transform
@@ -97,7 +98,6 @@ impl RendererInterface for Renderer {
                 v.position.y = self.viewport.h as f32
                     - (v.position.y + 1.0) * 0.5 * (self.viewport.h as f32 - 1.0)
                     + self.viewport.y as f32;
-                v.position.w = (v.position.w + 1.0) / 2.0;
             }
 
             // find AABB for triangle
@@ -153,11 +153,12 @@ impl RendererInterface for Renderer {
                 for i in 0..3 {
                     let mut v1 = vertices[i];
                     let mut v2 = vertices[(i + 1) % 3];
-                    v1.position.z = 1.0 / v1.position.z;
-                    v2.position.z = 1.0 / v2.position.z;
+
+                    shader::vertex_rhw_init(&mut v1);
+                    shader::vertex_rhw_init(&mut v2);
 
                     rasterize_line(
-                        &Line::new(v1, v2),
+                        &mut Line::new(v1, v2),
                         &self.shader.pixel_shading,
                         &self.uniforms,
                         texture_storage,
@@ -243,6 +244,10 @@ impl RendererInterface for Renderer {
     fn disable_framework(&mut self) {
         self.enable_framework = false;
     }
+
+    fn toggle_framework(&mut self) {
+        self.enable_framework = !self.enable_framework;
+    }
 }
 
 #[rustfmt::skip]

src/renderer.rs

@@ -50,6 +50,7 @@ pub trait RendererInterface {
     fn get_face_cull(&self) -> FaceCull;
     fn enable_framework(&mut self);
     fn disable_framework(&mut self);
+    fn toggle_framework(&mut self);
 }
 
 pub fn texture_sample(texture: &Texture, texcoord: &math::Vec2) -> math::Vec4 {
@@ -78,7 +79,7 @@ pub(crate) fn should_cull(
 }
 
 pub(crate) fn rasterize_line(
-    line: &Line,
+    line: &mut Line,
     shading: &shader::PixelShading,
     uniforms: &shader::Uniforms,
     texture_storage: &TextureStorage,
@@ -108,9 +109,9 @@ pub(crate) fn rasterize_line(
             let y = y as u32;
             if depth_attachment.get(x, y) <= z {
                 let mut attr = vertex.attributes;
-                shader::attributes_foreach(&mut attr, |value| value * z);
+                shader::attributes_foreach(&mut attr, |value| value / rhw);
                 // call pixel shading function to get shading color
-                let color = shading(&vertex.attributes, uniforms, texture_storage);
+                let color = shading(&attr, uniforms, texture_storage);
                 color_attachment.set(x, y, &color);
                 depth_attachment.set(x, y, z);
             }