feat(engine): add basic flat lighting

1 files changed, 64 insertions, 1 deletions

diff --git a/engine/src/renderer/mod.rs b/engine/src/renderer/mod.rs
index 7d5e104..d46612f 100644
--- a/engine/src/renderer/mod.rs
+++ b/engine/src/renderer/mod.rs
@@ -5,6 +5,8 @@ use cstr::cstr;
 use glfw::WindowSize;
 
 use crate::camera::Camera;
+use crate::color::Color;
+use crate::lighting::{LightSettings, LightSource};
 use crate::object::Object;
 use crate::opengl::buffer::{
     ArrayKind as ArrayBufferKind,
@@ -19,7 +21,7 @@ use crate::opengl::shader::Program as ShaderProgram;
 use crate::opengl::vertex_array::{PrimitiveKind, VertexArray};
 use crate::opengl::{clear_buffers, enable, BufferClearMask, Capability};
 use crate::projection::new_perspective;
-use crate::vector::Vec2;
+use crate::vector::{Vec2, Vec3};
 use crate::vertex::Vertex;
 
 #[derive(Debug)]
@@ -65,6 +67,8 @@ impl Renderer
     pub fn render<'obj>(
         &self,
         objects: impl IntoIterator<Item = &'obj Object>,
+        light_source: Option<&LightSource>,
+        light_settings: &LightSettings,
         window_size: &WindowSize,
     )
     {
@@ -81,6 +85,14 @@ impl Renderer
                         &shader_program_curr_bound,
                     );
 
+                    apply_light(
+                        obj,
+                        light_source,
+                        &self.camera,
+                        &shader_program_curr_bound,
+                        light_settings,
+                    );
+
                     if let Some(texture) = obj.texture() {
                         texture.inner().bind(|_| {
                             Self::draw_object(obj);
@@ -245,6 +257,57 @@ fn apply_transformation_matrices(
     );
 }
 
+fn apply_light(
+    obj: &Object,
+    light_source: Option<&LightSource>,
+    camera: &Camera,
+    shader_program_curr_bound: &CurrentlyBound<ShaderProgram>,
+    light_settings: &LightSettings,
+)
+{
+    obj.renderable().shader_program.set_uniform_vec_3fv(
+        shader_program_curr_bound,
+        cstr!("light_color"),
+        &light_source
+            .map_or(Color::WHITE_F32, |light_source| {
+                light_source.color().clone()
+            })
+            .into(),
+    );
+
+    obj.renderable().shader_program.set_uniform_vec_3fv(
+        shader_program_curr_bound,
+        cstr!("light_pos"),
+        &light_source.map_or_else(Vec3::default, |light_source| {
+            light_source.position().clone()
+        }),
+    );
+
+    obj.renderable().shader_program.set_uniform_1fv(
+        shader_program_curr_bound,
+        cstr!("ambient_light_strength"),
+        light_settings.ambient_light_strength,
+    );
+
+    obj.renderable().shader_program.set_uniform_1fv(
+        shader_program_curr_bound,
+        cstr!("specular_light_strength"),
+        light_settings.specular_light_strength,
+    );
+
+    obj.renderable().shader_program.set_uniform_1uiv(
+        shader_program_curr_bound,
+        cstr!("specular_shininess"),
+        light_settings.specular_shininess,
+    );
+
+    obj.renderable().shader_program.set_uniform_vec_3fv(
+        shader_program_curr_bound,
+        cstr!("view_pos"),
+        camera.position(),
+    );
+}
+
 #[cfg(feature = "debug")]
 #[tracing::instrument(skip_all)]
 fn opengl_debug_message_cb(