2020-08-29 23:50:38 +02:00
|
|
|
const std = @import("std");
|
2020-09-05 17:25:27 +02:00
|
|
|
const print = std.debug.print;
|
2021-05-10 23:30:34 +02:00
|
|
|
const Random = std.rand.Random;
|
2021-05-11 22:15:09 +02:00
|
|
|
|
2020-09-05 17:25:27 +02:00
|
|
|
const sdl = @import("sdl.zig");
|
|
|
|
const vec3 = @import("vec3.zig");
|
|
|
|
const Vec3 = vec3.Vec3;
|
|
|
|
const Point3 = vec3.Point3;
|
2021-04-26 22:51:49 +02:00
|
|
|
const color = @import("color.zig");
|
|
|
|
const Color = color.Color;
|
2020-09-05 17:25:27 +02:00
|
|
|
const Ray = @import("ray.zig").Ray;
|
2021-04-24 19:24:28 +02:00
|
|
|
const Sphere = @import("sphere.zig").Sphere;
|
|
|
|
const World = @import("world.zig").World;
|
2021-04-26 22:51:49 +02:00
|
|
|
const Camera = @import("camera.zig").Camera;
|
2021-05-11 22:15:09 +02:00
|
|
|
const material = @import("material.zig");
|
|
|
|
const Material = material.Material;
|
2020-08-30 20:05:00 +02:00
|
|
|
|
|
|
|
// From: https://github.com/Nelarius/weekend-raytracer-zig/blob/master/src/main.zig
|
|
|
|
// See https://github.com/zig-lang/zig/issues/565
|
|
|
|
// SDL_video.h:#define SDL_WINDOWPOS_UNDEFINED SDL_WINDOWPOS_UNDEFINED_DISPLAY(0)
|
|
|
|
// SDL_video.h:#define SDL_WINDOWPOS_UNDEFINED_DISPLAY(X) (SDL_WINDOWPOS_UNDEFINED_MASK|(X))
|
|
|
|
// SDL_video.h:#define SDL_WINDOWPOS_UNDEFINED_MASK 0x1FFF0000u
|
2020-09-05 17:25:27 +02:00
|
|
|
const SDL_WINDOWPOS_UNDEFINED = @bitCast(c_int, sdl.c.SDL_WINDOWPOS_UNDEFINED_MASK);
|
2020-08-30 20:05:00 +02:00
|
|
|
|
|
|
|
const fps = 60;
|
2020-08-29 23:50:38 +02:00
|
|
|
|
2021-04-24 17:45:08 +02:00
|
|
|
fn hitSphere(center: Point3, radius: f32, ray: Ray) f32 {
|
2020-09-18 13:55:48 +02:00
|
|
|
const ssr = ray.origin.sub(center); // Sphere-space ray, (A - C) in book
|
2021-04-24 17:59:17 +02:00
|
|
|
const a = ray.direction.length_squared();
|
|
|
|
const half_b = Vec3.dot(ssr, ray.direction);
|
|
|
|
const c = ssr.length_squared() - (radius * radius);
|
|
|
|
const discriminant = half_b * half_b - a * c;
|
2021-04-24 17:45:08 +02:00
|
|
|
if (discriminant < 0) {
|
|
|
|
return -1;
|
|
|
|
} else {
|
2021-04-24 17:59:17 +02:00
|
|
|
return (-half_b - std.math.sqrt(discriminant)) / a;
|
2021-04-24 17:45:08 +02:00
|
|
|
}
|
2020-09-18 13:55:48 +02:00
|
|
|
}
|
|
|
|
|
2021-05-10 23:30:34 +02:00
|
|
|
fn rayColor(ray: Ray, world: World, rng: *Random, depth: i32) Color {
|
|
|
|
// If we've exceeded the ray bounce limit, no more light is gathered.
|
|
|
|
if (depth <= 0) {
|
|
|
|
return Color{ .x = 0, .y = 0, .z = 0 };
|
|
|
|
}
|
|
|
|
|
|
|
|
if (world.hit(ray, 0.001, 99999)) |hit| {
|
2021-05-27 21:19:31 +02:00
|
|
|
if (material.scatter(ray, hit, rng)) |sRay| {
|
2021-05-11 22:15:09 +02:00
|
|
|
return sRay.color.mul(rayColor(sRay.ray, world, rng, depth - 1));
|
|
|
|
}
|
|
|
|
return Color{ .x = 0, .y = 0, .z = 0 };
|
2020-09-18 13:55:48 +02:00
|
|
|
}
|
2021-05-11 22:15:09 +02:00
|
|
|
const unitDirection = ray.direction.unit();
|
2021-04-24 19:24:28 +02:00
|
|
|
const t = 0.5 * (unitDirection.y + 1.0);
|
2020-09-05 17:25:27 +02:00
|
|
|
const white = Color{ .x = 1.0, .y = 1.0, .z = 1.0 };
|
|
|
|
const blue = Color{ .x = 0.5, .y = 0.7, .z = 1.0 };
|
2021-05-11 22:15:09 +02:00
|
|
|
return white.mul_s(1.0 - t).add(blue.mul_s(t));
|
2020-09-05 17:25:27 +02:00
|
|
|
}
|
|
|
|
|
2021-04-27 08:30:24 +02:00
|
|
|
fn setProgress(surface: *sdl.c.SDL_Surface, width: usize, height: usize, percent: f32) void {
|
|
|
|
if (percent == 1.0) {
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
const progressBarHeight = 3;
|
|
|
|
const progressWidth = @floatToInt(usize, @intToFloat(f32, width) * percent);
|
|
|
|
const progressColor = Color{ .x = 1.0 };
|
|
|
|
|
|
|
|
var j: usize = 0;
|
|
|
|
while (j < progressBarHeight) {
|
|
|
|
var i: usize = 0;
|
|
|
|
while (i < progressWidth) {
|
|
|
|
sdl.setSurfacePixel(surface, i, j, progressColor);
|
|
|
|
i += 1;
|
|
|
|
}
|
|
|
|
j += 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2021-05-28 19:51:05 +02:00
|
|
|
fn setupWorld(world: *World, rng: *Random) !void {
|
|
|
|
try world.spheres.append(Sphere{
|
|
|
|
.center = Point3{ .x = 0, .y = -1000, .z = 0 },
|
|
|
|
.radius = 1000,
|
|
|
|
.material = Material{ .lambertian = material.Lambertian{
|
|
|
|
.color = Color{ .x = 0.5, .y = 0.5, .z = 0.5 }
|
|
|
|
}}
|
|
|
|
});
|
|
|
|
|
|
|
|
var a: f32 = -11;
|
|
|
|
while (a < 11) : (a += 1) {
|
|
|
|
var b: f32 = -11;
|
|
|
|
while (b < 11) : (b += 1) {
|
|
|
|
const chooseMat = rng.float(f32);
|
|
|
|
const center = Point3{
|
|
|
|
.x = a + 0.9 * rng.float(f32),
|
|
|
|
.y = 0.2,
|
|
|
|
.z = b + 0.9 * rng.float(f32),
|
|
|
|
};
|
|
|
|
|
|
|
|
if (center.sub(Point3{ .x = 4, .y = 0.2 }).length() > 0.9) {
|
|
|
|
if (chooseMat < 0.8) {
|
|
|
|
// diffuse
|
|
|
|
try world.spheres.append(Sphere{
|
|
|
|
.center = center,
|
|
|
|
.radius = 0.2,
|
|
|
|
.material = Material{ .lambertian = material.Lambertian{
|
|
|
|
.color = Color{
|
|
|
|
.x = rng.float(f32) * rng.float(f32),
|
|
|
|
.y = rng.float(f32) * rng.float(f32),
|
|
|
|
.z = rng.float(f32) * rng.float(f32),
|
|
|
|
}
|
|
|
|
}},
|
|
|
|
});
|
|
|
|
} else if (chooseMat < 0.95) {
|
|
|
|
// metal
|
|
|
|
try world.spheres.append(Sphere{
|
|
|
|
.center = center,
|
|
|
|
.radius = 0.2,
|
|
|
|
.material = Material{ .metal = material.Metal{
|
|
|
|
.color = Color{
|
|
|
|
.x = 0.5 + rng.float(f32) / 2,
|
|
|
|
.y = 0.5 + rng.float(f32) / 2,
|
|
|
|
.z = 0.5 + rng.float(f32) / 2,
|
|
|
|
},
|
|
|
|
.fuzz = rng.float(f32) / 2,
|
|
|
|
}},
|
|
|
|
});
|
|
|
|
} else {
|
|
|
|
// glass
|
|
|
|
try world.spheres.append(Sphere{
|
|
|
|
.center = center,
|
|
|
|
.radius = 0.2,
|
|
|
|
.material = Material{ .dielectric = material.Dielectric{
|
|
|
|
.refraction_index = 1.5,
|
|
|
|
}},
|
|
|
|
});
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
try world.spheres.append(Sphere{
|
|
|
|
.center = Point3{ .x = 0, .y = 1, .z = 0 },
|
|
|
|
.radius = 1,
|
|
|
|
.material = Material{ .dielectric = material.Dielectric{
|
|
|
|
.refraction_index = 1.5
|
|
|
|
}},
|
|
|
|
});
|
|
|
|
|
|
|
|
try world.spheres.append(Sphere{
|
|
|
|
.center = Point3{ .x = -4, .y = 1, .z = 0 },
|
|
|
|
.radius = 1,
|
|
|
|
.material = Material{ .lambertian = material.Lambertian{
|
|
|
|
.color = Color{ .x = 0.4, .y = 0.2, .z = 0.1 }
|
|
|
|
}},
|
|
|
|
});
|
|
|
|
|
|
|
|
try world.spheres.append(Sphere{
|
|
|
|
.center = Point3{ .x = 4, .y = 1, .z = 0 },
|
|
|
|
.radius = 1,
|
|
|
|
.material = Material{ .metal = material.Metal{
|
|
|
|
.color = Color{ .x = 0.7, .y = 0.6, .z = 0.5 },
|
|
|
|
.fuzz = 0.0
|
|
|
|
}},
|
|
|
|
});
|
|
|
|
}
|
|
|
|
|
2020-08-29 23:50:38 +02:00
|
|
|
pub fn main() anyerror!void {
|
2020-09-05 17:25:27 +02:00
|
|
|
if (sdl.c.SDL_Init(sdl.c.SDL_INIT_VIDEO) != 0) {
|
|
|
|
std.log.err("Unable to initialize SDL: {}", .{sdl.c.SDL_GetError()});
|
2020-08-30 20:05:00 +02:00
|
|
|
return error.SDLInitializationFailed;
|
|
|
|
}
|
2020-09-05 17:25:27 +02:00
|
|
|
defer sdl.c.SDL_Quit();
|
|
|
|
|
2021-05-28 19:51:05 +02:00
|
|
|
var prng = std.rand.DefaultPrng.init(42);
|
|
|
|
|
|
|
|
|
2020-09-05 17:25:27 +02:00
|
|
|
// Image
|
2021-05-28 19:59:32 +02:00
|
|
|
const aspectRatio: f32 = 3.0 / 2.0;
|
2021-04-24 17:45:08 +02:00
|
|
|
const imageWidth = 600;
|
2020-09-05 17:25:27 +02:00
|
|
|
const imageHeight = @floatToInt(usize, imageWidth / aspectRatio);
|
2021-05-28 19:59:32 +02:00
|
|
|
const samplesPerPixel = 128;
|
|
|
|
const maxDepth = 16;
|
2020-09-05 17:25:27 +02:00
|
|
|
|
2021-04-24 19:24:28 +02:00
|
|
|
// World
|
2021-05-28 19:51:05 +02:00
|
|
|
var world = World.init();
|
|
|
|
defer world.deinit();
|
|
|
|
try setupWorld(&world, &prng.random);
|
2021-04-24 19:24:28 +02:00
|
|
|
|
2020-09-05 17:25:27 +02:00
|
|
|
// Camera
|
2021-05-28 19:51:05 +02:00
|
|
|
const lookFrom = Point3{ .x = 13, .y = 2, .z = 3 };
|
|
|
|
const lookAt = Point3{ .x = 0, .y = 0, .z = 0 };
|
2021-05-27 23:02:42 +02:00
|
|
|
const vup = Vec3{ .x = 0, .y = 1, .z = 0 };
|
2021-05-28 19:51:05 +02:00
|
|
|
const distToFocus = 10;
|
|
|
|
const aperture = 0.1;
|
2021-05-27 22:44:29 +02:00
|
|
|
const camera = Camera.init(
|
2021-05-27 23:02:42 +02:00
|
|
|
lookFrom,
|
|
|
|
lookAt,
|
|
|
|
vup,
|
2021-05-27 22:44:29 +02:00
|
|
|
20.0,
|
2021-05-27 23:02:42 +02:00
|
|
|
aspectRatio,
|
|
|
|
aperture,
|
|
|
|
distToFocus
|
2021-05-27 22:44:29 +02:00
|
|
|
);
|
2020-08-30 20:05:00 +02:00
|
|
|
|
2020-09-05 17:25:27 +02:00
|
|
|
const window = sdl.c.SDL_CreateWindow(
|
|
|
|
"Raytracing in One Weekend",
|
|
|
|
SDL_WINDOWPOS_UNDEFINED,
|
|
|
|
SDL_WINDOWPOS_UNDEFINED,
|
|
|
|
imageWidth,
|
|
|
|
imageHeight,
|
|
|
|
sdl.c.SDL_WINDOW_OPENGL
|
|
|
|
) orelse {
|
|
|
|
std.log.err("Unable to create window: {}", .{sdl.c.SDL_GetError()});
|
2020-08-30 20:05:00 +02:00
|
|
|
return error.SDLInitializationFailed;
|
|
|
|
};
|
|
|
|
|
2020-09-05 17:25:27 +02:00
|
|
|
const surface = sdl.c.SDL_GetWindowSurface(window) orelse {
|
|
|
|
std.log.err("Unable to get window surface: {}", .{sdl.c.SDL_GetError()});
|
2020-08-30 20:05:00 +02:00
|
|
|
return error.SDLInitializationFailed;
|
|
|
|
};
|
|
|
|
|
2021-04-26 23:50:14 +02:00
|
|
|
var pixelAccu: [imageWidth * imageHeight]Color = undefined;
|
|
|
|
for (pixelAccu) |*pixel| {
|
|
|
|
pixel.* = Color{};
|
|
|
|
}
|
2021-04-26 22:51:49 +02:00
|
|
|
|
2020-09-05 17:25:27 +02:00
|
|
|
if (sdl.c.SDL_UpdateWindowSurface(window) != 0) {
|
|
|
|
std.log.err("Error updating window surface: {}", .{sdl.c.SDL_GetError()});
|
2020-08-30 20:05:00 +02:00
|
|
|
return error.SDLUpdateWindowFailed;
|
|
|
|
}
|
|
|
|
|
|
|
|
var running = true;
|
2021-04-27 08:30:24 +02:00
|
|
|
var k: usize = 0;
|
2020-08-30 20:05:00 +02:00
|
|
|
while (running) {
|
2020-09-05 17:25:27 +02:00
|
|
|
var event: sdl.c.SDL_Event = undefined;
|
|
|
|
while (sdl.c.SDL_PollEvent(&event) != 0) {
|
2020-08-30 20:05:00 +02:00
|
|
|
switch (event.@"type") {
|
2020-09-05 17:25:27 +02:00
|
|
|
sdl.c.SDL_QUIT => {
|
2020-08-30 20:05:00 +02:00
|
|
|
running = false;
|
|
|
|
},
|
|
|
|
else => {},
|
|
|
|
}
|
|
|
|
}
|
2021-04-27 08:30:24 +02:00
|
|
|
|
2021-04-27 09:05:46 +02:00
|
|
|
if (k < samplesPerPixel) {
|
|
|
|
|
|
|
|
// Render
|
|
|
|
_ = sdl.c.SDL_LockSurface(surface);
|
|
|
|
|
|
|
|
var j: usize = 0;
|
|
|
|
while (j < imageHeight) {
|
|
|
|
var i: usize = 0;
|
|
|
|
while (i < imageWidth) {
|
|
|
|
var imageIndex = i + j * imageWidth;
|
|
|
|
var pixelColor = &pixelAccu[imageIndex];
|
2021-04-27 08:30:24 +02:00
|
|
|
|
2021-04-27 09:05:46 +02:00
|
|
|
const u = (@intToFloat(f32, i) + prng.random.float(f32)) / @intToFloat(f32, (imageWidth - 1));
|
|
|
|
const v = (@intToFloat(f32, j) + prng.random.float(f32)) / @intToFloat(f32, (imageHeight - 1));
|
2021-05-27 23:02:42 +02:00
|
|
|
const r = camera.getRay(u, v, &prng.random);
|
2021-05-10 23:30:34 +02:00
|
|
|
const sample = rayColor(r, world, &prng.random, maxDepth);
|
2021-04-27 09:05:46 +02:00
|
|
|
pixelColor.* = pixelColor.*.add(sample);
|
2021-04-27 08:30:24 +02:00
|
|
|
|
2021-04-27 09:05:46 +02:00
|
|
|
const averageColor = color.averageColor(pixelColor, @intCast(i32, k));
|
|
|
|
// SDL coordinate system is flipped compared to the raytracer
|
|
|
|
sdl.setSurfacePixel(surface, i, imageHeight - 1 - j, averageColor);
|
|
|
|
|
|
|
|
i += 1;
|
|
|
|
}
|
|
|
|
j += 1;
|
2021-04-27 08:30:24 +02:00
|
|
|
}
|
|
|
|
|
2021-04-27 09:05:46 +02:00
|
|
|
setProgress(surface, imageWidth, imageHeight, @intToFloat(f32, k + 1) / @intToFloat(f32, samplesPerPixel));
|
|
|
|
|
|
|
|
sdl.c.SDL_UnlockSurface(surface);
|
|
|
|
_ = sdl.c.SDL_UpdateWindowSurface(window);
|
|
|
|
k += 1;
|
|
|
|
|
|
|
|
} else {
|
|
|
|
|
2021-04-27 08:30:24 +02:00
|
|
|
sdl.c.SDL_Delay(1000 / fps);
|
2021-04-27 09:05:46 +02:00
|
|
|
|
2021-04-27 08:30:24 +02:00
|
|
|
}
|
2020-08-30 20:05:00 +02:00
|
|
|
}
|
2020-08-29 23:50:38 +02:00
|
|
|
}
|