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const std = @import("std");
const rl = @import("raylib");
const particle = struct {
color: rl.Color,
attrs: particleAttrs,
x: i32,
y: i32,
xvel: i32,
yvel: i32,
};
const particleAttrs = struct {};
const screenWidth = 1920;
const screenHeight = 1080;
const particleMax = 5000;
pub fn main() !void {
rl.initWindow(screenWidth, screenHeight, "Particle Simulator");
defer rl.closeWindow();
rl.setTargetFPS(60);
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
defer _ = gpa.deinit();
var particles = try initParticles(gpa.allocator(), 1);
defer particles.deinit(gpa.allocator());
while (!rl.windowShouldClose()) {
rl.beginDrawing();
if (rl.isKeyPressed(rl.KeyboardKey.key_q)) break;
defer rl.endDrawing();
for (particles.items(.y), particles.items(.yvel)) |*y, yvel|
y.* = @mod((y.* + yvel), screenHeight);
for (particles.items(.x), particles.items(.xvel)) |*x, xvel|
x.* = @mod((x.* + xvel), screenWidth);
for (particles.items(.y), particles.items(.x), particles.items(.color)) |*y, *x, color|
rl.drawRectangle(x.*, y.*, 1, 1, color);
if (particles.slice().len < particleMax) try particles.append(gpa.allocator(), createParticle(.{}));
std.debug.print("{}\n", .{particles.slice().len});
rl.clearBackground(rl.Color.black);
}
}
/// Generates a particle with a random Color and Location
pub fn createParticle(attrs: particleAttrs) particle {
const seed = @as(u64, @truncate(@as(u128, @bitCast(std.time.nanoTimestamp()))));
var prng = std.rand.DefaultPrng.init(seed);
const colors = [_]rl.Color{ rl.Color.red, rl.Color.blue, rl.Color.green };
const x = prng.random().uintLessThan(u32, screenWidth);
const y = prng.random().uintLessThan(u32, screenHeight);
const color = colors[prng.random().uintLessThan(u32, 3)];
return particle{
.color = color,
.attrs = attrs,
.x = @intCast(x),
.y = @intCast(y),
.xvel = 5,
.yvel = -7,
};
}
/// Initialize a MultiArrayList of size amnt with particles created by createParticle
pub fn initParticles(allocator: std.mem.Allocator, amnt: u32) !std.MultiArrayList(particle) {
var particles = std.MultiArrayList(particle){};
try particles.setCapacity(allocator, 10000);
for (0..amnt) |_| {
try particles.append(allocator, createParticle(.{}));
}
return particles;
}
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