diff options
author | Tom Barrett <tom@tombarrett.xyz> | 2022-12-24 18:31:35 +0100 |
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committer | Tom Barrett <tom@tombarrett.xyz> | 2022-12-24 18:31:35 +0100 |
commit | 39b57fa0729d16873193947b12e59a7da52695fa (patch) | |
tree | 2c10fa22ab5f27e4db80732aa55166e42ffc7de6 | |
parent | 8ab21b7ec6bd83fe12b48534e4f670500e8d5e2c (diff) |
more ziglike
-rw-r--r-- | src/main.zig | 37 | ||||
-rw-r--r-- | src/vec.zig | 16 |
2 files changed, 28 insertions, 25 deletions
diff --git a/src/main.zig b/src/main.zig index e2b63d2..5f6ea29 100644 --- a/src/main.zig +++ b/src/main.zig @@ -2,28 +2,18 @@ const std = @import("std"); const warn = @import("std").debug.print; const vec = @import("vec.zig"); -pub fn ray_color(r: ray) vec.vec { - if (hit_sphere(vec.init(0, 0, -1), 0.5, r)) |t| { - const n = vec.unit_vector(r.origin + vec.scalar(t) * r.direction - vec.init(0, 0, -1)); - return vec.scalar(0.5) * vec.init(n[0] + 1, n[1] + 1, n[2] + 1); - } - const direction = vec.unit_vector(r.direction); - const t = 0.5 * (direction[1] + 1.0); - return vec.scalar(1.0 - t) * vec.init(1.0, 1.0, 1.0) + vec.scalar(t) * vec.init(0.5, 0.7, 1.0); -} - -pub fn write_color(stdout: anytype, v: vec.vec) !void { +pub fn writeColor(stdout: anytype, v: vec.Vec) !void { const r = @floatToInt(usize, v[0] * 255.999); const g = @floatToInt(usize, v[1] * 255.999); const b = @floatToInt(usize, v[2] * 255.999); try stdout.print("{} {} {}\n", .{ r, g, b }); } -pub fn hit_sphere(center: vec.vec, radius: f32, r: ray) ?f32 { +pub fn hitSphere(center: vec.Vec, radius: f32, r: Ray) ?f32 { const oc = r.origin - center; - const a = vec.length_squared(r.direction); + const a = vec.lengthSquared(r.direction); const half_b = vec.dot(oc, r.direction); - const c = vec.length_squared(oc) - radius * radius; + const c = vec.lengthSquared(oc) - radius * radius; const discriminant = half_b * half_b - a * c; if (discriminant < 0) { return null; @@ -32,7 +22,20 @@ pub fn hit_sphere(center: vec.vec, radius: f32, r: ray) ?f32 { } } -const ray = struct { origin: vec.vec, direction: vec.vec }; +const Ray = struct { + origin: vec.Vec, + direction: vec.Vec, + + pub fn color(self: Ray) vec.Vec { + if (hitSphere(vec.init(0, 0, -1), 0.5, self)) |t| { + const n = vec.unitVec(self.origin + vec.scalar(t) * self.direction - vec.init(0, 0, -1)); + return vec.scalar(0.5) * vec.init(n[0] + 1, n[1] + 1, n[2] + 1); + } + const direction = vec.unitVec(self.direction); + const t = 0.5 * (direction[1] + 1.0); + return vec.scalar(1.0 - t) * vec.init(1.0, 1.0, 1.0) + vec.scalar(t) * vec.init(0.5, 0.7, 1.0); + } +}; pub fn main() !void { const aspect_ratio: f32 = 16.0 / 9.0; @@ -59,9 +62,9 @@ pub fn main() !void { while (i < width) : (i += 1) { var u = vec.scalar(@intToFloat(f32, i) / @intToFloat(f32, width - 1)); var v = vec.scalar(@intToFloat(f32, j) / @intToFloat(f32, height - 1)); - var color = ray_color(ray{ .origin = origin, .direction = lower_left_corner + u * horizontal + v * vertical - origin }); + var r = Ray{ .origin = origin, .direction = lower_left_corner + u * horizontal + v * vertical - origin }; - try write_color(stdout, color); + try writeColor(stdout, r.color()); } } try bw.flush(); diff --git a/src/vec.zig b/src/vec.zig index cc245a4..b98f9f4 100644 --- a/src/vec.zig +++ b/src/vec.zig @@ -1,25 +1,25 @@ -pub const vec = @Vector(3, f32); +pub const Vec = @Vector(3, f32); -pub fn init(x: f32, y: f32, z: f32) vec { +pub fn init(x: f32, y: f32, z: f32) Vec { return @Vector(3, f32){ x, y, z }; } -pub fn scalar(x: f32) vec { +pub fn scalar(x: f32) Vec { return @splat(3, x); } -pub fn unit_vector(v: vec) vec { +pub fn unitVec(v: Vec) Vec { return v / scalar(length(v)); } -pub fn length_squared(v: vec) f32 { +pub fn lengthSquared(v: Vec) f32 { return v[0] * v[0] + v[1] * v[1] + v[2] * v[2]; } -pub fn length(v: vec) f32 { - return @sqrt(length_squared(v)); +pub fn length(v: Vec) f32 { + return @sqrt(lengthSquared(v)); } -pub fn dot(x: vec, y: vec) f32 { +pub fn dot(x: Vec, y: Vec) f32 { return x[0] * y[0] + x[1] * y[1] + x[2] * y[2]; } |