Optimize calcul

Miou-zora · May 8, 2024 · 350591e · 350591e
1 parent 5800379
commit 350591e
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Showing 4 changed files with 18 additions and 21 deletions.
diff --git a/src/Cylinder.zig b/src/Cylinder.zig
@@ -16,11 +16,10 @@ pub const Cylinder = struct {
     transform: ?Transform = null,
 
     pub fn hits(self: *const Self, ray: Ray) HitRecord {
-        const rx_minus_cx = ray.origin[0] - self.origin[0];
-        const ry_minus_cy = ray.origin[1] - self.origin[1];
-        const a = ray.direction[0] * ray.direction[0] + ray.direction[1] * ray.direction[1];
-        const b = 2.0 * (ray.direction[0] * rx_minus_cx + ray.direction[1] * ry_minus_cy);
-        const c = rx_minus_cx * rx_minus_cx + ry_minus_cy * ry_minus_cy - self.radius * self.radius;
+        const r_minus_c = ray.origin - self.origin;
+        const a = zmath.dot2(ray.direction, ray.direction)[0] * 2; // Good luck to understand this, I don't
+        const b = zmath.dot2(ray.direction, r_minus_c)[0] * 4;
+        const c = zmath.dot2(r_minus_c, r_minus_c)[0] * 2 - self.radius * self.radius;
 
         const delta = b * b - 4.0 * a * c;
         if (delta < 0.0 or a == 0.0) {
@@ -31,9 +30,10 @@ pub const Cylinder = struct {
             if (t < 0.0) {
                 return HitRecord.nil();
             } else {
+                const normal = intersection_point - self.origin;
                 return HitRecord{
                     .hit = true,
-                    .normal = zmath.f32x4(intersection_point[0] - self.origin[0], intersection_point[1] - self.origin[1], 0, 0),
+                    .normal = zmath.f32x4(normal[0], normal[1], 0, 0),
                     .intersection_point = intersection_point,
                     .t = zmath.length3(intersection_point - ray.origin)[0],
                     .material = self.material,
@@ -47,9 +47,10 @@ pub const Cylinder = struct {
             }
             const t = if (t1 < t2 and t1 > 0) t1 else t2;
             const intersection_point = zmath.mulAdd(ray.direction, @as(Vec3, @splat(t)), ray.origin);
+            const normal = intersection_point - self.origin;
             return HitRecord{
                 .hit = true,
-                .normal = zmath.f32x4(intersection_point[0] - self.origin[0], intersection_point[1] - self.origin[1], 0, 0),
+                .normal = zmath.f32x4(normal[0], normal[1], 0, 0),
                 .intersection_point = intersection_point,
                 .t = zmath.length3(intersection_point - ray.origin)[0],
                 .material = self.material,

diff --git a/src/Plane.zig b/src/Plane.zig
@@ -21,13 +21,13 @@ pub const Plane = struct {
     }
 
     pub fn hits(self: *const Self, ray: Ray) HitRecord {
-        const denom = @reduce(.Add, self.normal * ray.direction);
+        const denom: f32 = zmath.dot3(self.normal, ray.direction)[0];
 
         if (denom == 0.0) {
             return HitRecord.nil();
         }
 
-        const t = @reduce(.Add, (self.origin - ray.origin) * self.normal) / denom;
+        const t: f32 = zmath.dot3(self.origin - ray.origin, self.normal)[0] / denom;
 
         if (t < 0.0) {
             return HitRecord.nil();

diff --git a/src/Triangle.zig b/src/Triangle.zig
@@ -42,17 +42,19 @@ pub const Triangle = struct {
         const aSubc = a - c;
         const cSubb = c - b;
 
-        const u = @reduce(.Add, zmath.cross3(bSuba, hit_point - a) * normal);
-        const v = @reduce(.Add, zmath.cross3(cSubb, hit_point - b) * normal);
-        const w = @reduce(.Add, zmath.cross3(aSubc, hit_point - c) * normal);
+        const u = zmath.dot3(zmath.cross3(bSuba, hit_point - a), normal)[0];
+        const v = zmath.dot3(zmath.cross3(cSubb, hit_point - b), normal)[0];
+        const w = zmath.dot3(zmath.cross3(aSubc, hit_point - c), normal)[0];
 
         if (u < 0 or v < 0 or w < 0) {
             return HitRecord.nil();
         }
-
+        const barycentric = zmath.f32x4(u, v, w, 0);
+        const texCoord1 = zmath.f32x4(self.va.texCoord[0], self.vb.texCoord[0], self.vc.texCoord[0], 0); // Is it efficient to store this in tmp const?
+        const texCoord2 = zmath.f32x4(self.va.texCoord[1], self.vb.texCoord[1], self.vc.texCoord[1], 0); // same
         const posInImage: @Vector(2, usize) = .{
-            @as(usize, @intFromFloat((u * self.va.texCoord[0] + v * self.vb.texCoord[0] + w * self.vc.texCoord[0]) / (u + v + w) * @as(f32, @floatFromInt(self.text.rlImage.width)))),
-            @as(usize, @intFromFloat((u * self.va.texCoord[1] + v * self.vb.texCoord[1] + w * self.vc.texCoord[1]) / (u + v + w) * @as(f32, @floatFromInt(self.text.rlImage.height)))),
+            @as(usize, @intFromFloat(@reduce(.Add, barycentric * texCoord1) / @reduce(.Add, barycentric) * @as(f32, @floatFromInt(self.text.rlImage.width)))),
+            @as(usize, @intFromFloat(@reduce(.Add, barycentric * texCoord2) / @reduce(.Add, barycentric) * @as(f32, @floatFromInt(self.text.rlImage.height)))),
         };
         const cInt_to_usize = @as(usize, @intCast(self.text.rlImage.width));
         const color: rl.Color = self.text.rlColors[posInImage[1] * cInt_to_usize + posInImage[0]];

diff --git a/src/main.zig b/src/main.zig
@@ -91,12 +91,6 @@ fn get_pixel_color(ray: Ray, scene: *Scene.Scene, height: u32, width: u32, recur
         width,
         recursion_depth - 1,
     );
-    // return .{
-    //     .r = @as(u8, @intFromFloat(@as(f32, @floatFromInt(color.r)) * (1 - reflective) + @as(f32, @floatFromInt(reflected_color.r)) * reflective)),
-    //     .g = @as(u8, @intFromFloat(@as(f32, @floatFromInt(color.g)) * (1 - reflective) + @as(f32, @floatFromInt(reflected_color.g)) * reflective)),
-    //     .b = @as(u8, @intFromFloat(@as(f32, @floatFromInt(color.b)) * (1 - reflective) + @as(f32, @floatFromInt(reflected_color.b)) * reflective)),
-    //     .a = 255,
-    // };
     return color * @as(Vec3, @splat(1 - reflective)) + reflected_color * @as(Vec3, @splat(reflective));
 }