From 39b57fa0729d16873193947b12e59a7da52695fa Mon Sep 17 00:00:00 2001 From: Tom Barrett Date: Sat, 24 Dec 2022 18:31:35 +0100 Subject: more ziglike --- src/main.zig | 37 ++++++++++++++++++++----------------- 1 file changed, 20 insertions(+), 17 deletions(-) (limited to 'src/main.zig') 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(); -- cgit v1.2.3