rotation , but it looks weird

1 files changed, 128 insertions, 4 deletions

diff --git a/src/main.rs b/src/main.rs
index fdd2f54..dc29e2b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,18 +1,134 @@
+extern crate nalgebra;
+
 mod sdl;
 pub mod win;
+pub mod sdf;
+
+use nalgebra::{Vector3, Matrix3, Rotation3};
+type Vec3 = Vector3<f32>;
+type Mat3 = Matrix3<f32>;
+type Rot3 = Rotation3<f32>;
+
+struct View {
+	pos: Vec3,
+	yaw: f32,
+	pitch: f32
+}
+
+impl Default for View {
+	fn default() -> Self {
+		Self {
+			pos: Vec3::zeros(),
+			yaw: 0.0,
+			pitch: 0.0
+		}
+	}
+}
+
+impl View {
+	/// `camera_rotation() * vec3(0, 0, -1)` is the direction the camera is pointing
+	fn camera_rotation(&self) -> Mat3 {
+		*Rot3::from_euler_angles(self.pitch, self.yaw, 0.0).matrix()
+	}
+}
+
 
 fn try_main() -> Result<(), String> {
+	let my_sdf = sdf::Sdf::sphere();
+
 	let mut window = win::Window::new("AutoSDF", 1280, 720, true)
 		.map_err(|e| format!("Error creating window: {e}"))?;
 	
+	let mut fshader_source = String::new();
+	fshader_source.push_str("
+IN vec2 pos;
+uniform vec3 u_camera_position;
+uniform mat3 u_camera_rotation;
+");
+	my_sdf.to_glsl(&mut fshader_source);
+	fshader_source.push_str("
+#define ITERATIONS 30
+#define AA_X 2
+#define AA_Y 2
+
+
+
+float fbm(vec3 p) {
+    float t = 0.0;
+    float freq = 24.0;
+    mat3 m = mat3(cos(1.),sin(1.),0,
+                 -sin(1.),cos(1.),0,
+                 0,            0, 1) * mat3(
+                  1,           0, 0,
+                  0,      cos(1.),sin(1.),
+                  0,     -sin(1.),cos(1.)
+    );
+    for(int i = 0; i < 5; i++)
+    {
+        p = m * p;
+        t += pow(0.6, float(i)) * sin(freq*p.x)*sin(freq*p.y)*sin(freq*p.z);
+        freq *= 2.0;
+    }
+    return t;
+}
+		
+vec3 normal(vec3 p)
+{
+// thanks to https://iquilezles.org/articles/normalsSDF/
+    float h = 0.0001;
+    vec2 k = vec2(1.,-1.);
+    vec3 sdf_normal = k.xyy*sdf(p + k.xyy*h) + 
+                      k.yyx*sdf(p + k.yyx*h) + 
+                      k.yxy*sdf(p + k.yxy*h) + 
+                      k.xxx*sdf(p + k.xxx*h);
+    vec3 noise_normal = k.xyy*fbm(p + k.xyy*h) + 
+                        k.yyx*fbm(p + k.yyx*h) + 
+                        k.yxy*fbm(p + k.yxy*h) + 
+                        k.xxx*fbm(p + k.xxx*h);
+    return normalize(sdf_normal + 0.003 * noise_normal);
+}
+
+void main() {
+	float focal_length = 0.3;
+	float min_dist = 10.;
+	vec2 inv_screen_size = 1.0 / vec2(1280.0, 720.0); // @TODO
+	vec2 aa_delta = inv_screen_size / vec2(AA_X, AA_Y);
+	vec3 final_color = vec3(0);
+	for (int m = 0; m < AA_X; m++) {
+	for (int n = 0; n < AA_Y; n++) {
+	vec3 p = u_camera_position;
+	vec2 aa_offset = vec2(float(m), float(n)) * aa_delta;
+	vec3 delta = normalize(u_camera_rotation * vec3(pos + aa_offset, -focal_length));
+	int i;
+	for (i = 0; i < ITERATIONS; i++) {
+		float dist = sdf(p);
+		min_dist = min(min_dist, dist);
+		if (dist <= 0.01) {
+			float L = 0.3 + max(0., dot(normal(p), normalize(vec3(.8,1,.6))));
+			final_color += L * vec3(1.0, 0.0, 0.0);
+			
+			break;
+		} 
+		p += dist * delta;
+	}
+	}
+	}
+	final_color *= 1.0 / (AA_X * AA_Y);
+	o_color = vec4(final_color, 1.0);
+}");
+	
+	println!("{fshader_source}");
+	
 	let program = window.create_program(
 		"attribute vec2 v_pos;
+		OUT vec2 pos;
+		uniform float u_aspect_ratio;
+		
 		void main() {
+			pos = v_pos * vec2(u_aspect_ratio, 1.0);
 			gl_Position = vec4(v_pos, 0.0, 1.0);
 		}",
-		"void main() {
-			o_color = vec4(1.0, 0.0, 0.0, 1.0);
-		}"
+		&fshader_source
 	).map_err(|e| format!("Error compiling shader:\n{e}"))?;
 	
 	let mut buffer = window.create_buffer();
@@ -28,6 +144,8 @@ fn try_main() -> Result<(), String> {
 	let mut array = window.create_vertex_array(buffer, &program);
 	window.array_attrib2f(&mut array, "v_pos", 0);
 	
+	let mut view = View::default();
+	
 	'mainloop: loop {
 		while let Some(event) = window.next_event() {
 			use win::Event::*;
@@ -35,11 +153,17 @@ fn try_main() -> Result<(), String> {
 				Quit => break 'mainloop,
 				_ => {},
 			}
-			println!("{event:?}");
 		}
 		
+		window.viewport_full_screen();
+		
+		view.yaw += 0.002;
+		
 		window.clear_screen(win::ColorF32::BLACK);
 		window.use_program(&program);
+		window.uniform1f("u_aspect_ratio", window.aspect_ratio());
+		window.uniform3f("u_camera_position", view.pos.x, view.pos.y, view.pos.z);
+		window.uniform3x3f("u_camera_rotation", view.camera_rotation().as_slice());
 		
 		window.draw_array(&array);