ref: e3c2fff3fead8501068149464c2716ed5f06a594
parent: ccccea5a7cb177a440075a711c12272096c2bc77
author: Jacob G-W <jacoblevgw@gmail.com>
date: Wed Jul 19 18:25:49 EDT 2023
add bouncing example
binary files /dev/null b/bouncing differ
--- a/build.sh
+++ b/build.sh
@@ -1,3 +1,3 @@
#!/usr/bin/env bash
# just a temporary fix until the x86_64 backend supports build.zig
-~/dev/zig/build/debug/bin/zig build-exe examples/main.zig --main-pkg-path . -target x86_64-plan9-none -freference-trace -fsingle-threaded --zig-lib-dir ~/dev/zig/lib
+~/dev/zig/build/debug/bin/zig build-exe "examples/$1.zig" --main-pkg-path . -target x86_64-plan9-none -freference-trace -fsingle-threaded --zig-lib-dir ~/dev/zig/lib
--- /dev/null
+++ b/examples/bouncing.zig
@@ -1,0 +1,53 @@
+const std = @import("std");+const ld = @import("../src/libdraw.zig");+const Point = ld.Point;
+const Rectangle = ld.Rectangle;
+var colors: [15]*ld.Image = undefined;
+const cs: [15]u32 = .{+ 0xff0000ff,
+ 0xff3600ff,
+ 0xff6d00ff,
+ 0xffa400ff,
+ 0xffda00ff,
+ 0xdbff00ff,
+ 0x6dff00ff,
+ 0x00ff00ff,
+ 0x00926dff,
+ 0x0024dbff,
+ 0x1500dbff,
+ 0x3600a6ff,
+ 0x540094ff,
+ 0x7000c9ff,
+ 0x8b00ffff,
+};
+pub fn main() !void {+ const ally = std.heap.page_allocator;
+ const d = ld.initDraw(ally, null, "balls") catch |e| {+ std.debug.print("errstr: {s}\n", .{std.os.plan9.errstr()});+ return e;
+ };
+ defer d.close() catch {};+ for (cs, &colors) |c, *color| {+ color.* = try d.allocImage(Rectangle.init(0, 0, 1, 1), .rgba32, true, c);
+ }
+ var frames: usize = 0;
+ const screen = d.getScreen();
+ var ball: ld.Point = .{ .x = @divFloor((screen.r.max.x + screen.r.min.x), 2), .y = screen.r.max.y };+ var vel: ld.Point = .{ .x = 2, .y = -1 };+ while (true) {+ frames += 1;
+ try screen.draw(screen.r, d.white, null, ld.Point.Zero);
+ try screen.ellipse(ball, 8, 8, 8, colors[@divFloor(frames, 30) % 15], ld.Point.Zero);
+ ball.x += vel.x;
+ ball.y += vel.y;
+ vel.y += 2;
+ if (ball.y > screen.r.max.y) {+ vel.y *= -1;
+ }
+ if (ball.x < screen.r.min.x or ball.x > screen.r.max.x) {+ vel.x *= -1;
+ }
+ try d.flushImage(true);
+ _ = std.os.plan9.syscall_bits.syscall1(.SLEEP, 20);
+ }
+}
--- a/examples/main.zig
+++ b/examples/main.zig
@@ -1,7 +1,86 @@
const std = @import("std"); const ld = @import("../src/libdraw.zig");const SQUARELEN = 40;
-const SPACING = 10;
+const SPACING = 15;
+const Point = ld.Point;
+const Rectangle = ld.Rectangle;
+const Ball = struct {+ const FPoint = struct {+ x: f32,
+ y: f32,
+ fn toPoint(self: @This()) Point {+ return .{ .x = @intFromFloat(self.x), .y = @intFromFloat(self.y) };+ }
+ };
+ pos: FPoint,
+ vel: FPoint,
+ fn collide(b: *Ball) void {+ var i: u16 = 0;
+ while (i < numbricks_vert) : (i += 1) {+ var j: u16 = 0;
+ while (j < numbricks_horiz) : (j += 1) {+ const val = bricks[i * numbricks_vert + j];
+ if (val == 0) continue;
+ switch (b.testCollide(i, j)) {+ .horiz => {+ bricks[i * numbricks_vert + j] -|= 1;
+ b.vel.y *= -1;
+ return;
+ },
+ .vert => {+ bricks[i * numbricks_vert + j] -|= 1;
+ b.vel.x *= -1;
+ return;
+ },
+ .none => {},+ }
+ }
+ }
+ }
+ fn testCollide(self: Ball, i: u16, j: u16) enum { horiz, vert, none } {+ const brick = getBrickRect(i, j);
+ const p = self.pos.toPoint();
+ const brickcenter: Point = .{ .x = brick.min.x + @divFloor(brick.width(), 2), .y = @divFloor(brick.min.y + brick.height(), 2) };+ if (p.x >= brick.min.x and
+ p.x <= brick.max.x and
+ p.y >= brick.min.y and
+ p.y <= brick.max.y)
+ {+ // const a = std.math.radiansToDegrees(f32, std.math.atan2(f32, @as(f32, @floatFromInt(brickcenter.y - p.y)), @as(f32, @floatFromInt(brickcenter.x - p.x))));
+ // if (@fabs(a) < 45 or @fabs(a) >= 135) return .horiz;
+ // return .vert;
+ if (std.math.absInt(p.x - brickcenter.x) catch unreachable < std.math.absInt(p.y - brickcenter.y) catch unreachable) return .vert;
+ return .horiz;
+ }
+ return .none;
+ }
+};
+var bricks: []u32 = undefined;
+var screenr: ld.Rectangle = undefined;
+var balls: std.ArrayList(Ball) = undefined;
+var numbricks_vert: u32 = undefined;
+var numbricks_horiz: u32 = undefined;
+var colors: [15]*ld.Image = undefined;
+const cs: [15]u32 = .{+ 0xff0000ff,
+ 0xff3600ff,
+ 0xff6d00ff,
+ 0xffa400ff,
+ 0xffda00ff,
+ 0xdbff00ff,
+ 0x6dff00ff,
+ 0x00ff00ff,
+ 0x00926dff,
+ 0x0024dbff,
+ 0x1500dbff,
+ 0x3600a6ff,
+ 0x540094ff,
+ 0x7000c9ff,
+ 0x8b00ffff,
+};
+fn getBrickRect(i: u16, j: u16) Rectangle {+ return Rectangle.init(screenr.min.x + SQUARELEN * j, screenr.min.y + SQUARELEN * i, screenr.min.x + SQUARELEN * (j + 1) - SPACING, screenr.min.y + SQUARELEN * (i + 1) - SPACING);
+}
pub fn main() !void {const ally = std.heap.page_allocator;
const d = ld.initDraw(ally, null, "balls") catch |e| {@@ -12,37 +91,57 @@
const screen = d.getScreen();
const width = screen.r.width();
const height = screen.r.height();
- const numsquares_horiz: u32 = @intCast(@divFloor(width, SQUARELEN));
- const numsquares_vert: u32 = @intCast(@divFloor(height, SQUARELEN) - 3);
- var squares = try ally.alloc(u32, numsquares_horiz * numsquares_vert);
- for (squares) |*square| {- square.* = 10;
+ for (cs, &colors) |c, *color| {+ color.* = try d.allocImage(Rectangle.init(0, 0, 1, 1), .rgba32, true, c);
}
- const screenr = screen.r;
- try d.flushImage(true);
- var ball: ld.Point = .{ .x = @divFloor(screenr.min.x + screenr.max.x, 2), .y = screenr.max.y };- var ballv: ld.Point = .{ .x = 1, .y = -1 };+ screenr = screen.r;
+ numbricks_horiz = @intCast(@divFloor(width, SQUARELEN));
+ numbricks_vert = @intCast(@divFloor(height, SQUARELEN) - 3);
+ bricks = try ally.alloc(u32, numbricks_horiz * numbricks_vert);
+ for (bricks) |*square| {+ square.* = 14;
+ }
+ balls = try std.ArrayList(Ball).initCapacity(ally, 40);
+ // var angle: f32 = std.math.degreesToRadians(f32, 80);
+ // try balls.append(.{ .pos = .{ .x = @divFloor(screenr.min.x + screenr.max.x, 2), .y = screenr.max.y }, .vel = .{ .x = @cos(angle), .y = @sin(angle) } });+ try balls.append(.{ .pos = .{ .x = @as(f32, @floatFromInt(screenr.min.x + screenr.max.x)) / 2.0, .y = @as(f32, @floatFromInt(screenr.max.y)) }, .vel = .{ .x = 3.4, .y = 2.8 } });+ try balls.append(.{ .pos = .{ .x = @as(f32, @floatFromInt(screenr.min.x + screenr.max.x)) / 2.0, .y = @as(f32, @floatFromInt(screenr.max.y)) }, .vel = .{ .x = 1.4, .y = 7.8 } });+ try balls.append(.{ .pos = .{ .x = @as(f32, @floatFromInt(screenr.min.x + screenr.max.x)) / 2.0, .y = @as(f32, @floatFromInt(screenr.max.y)) }, .vel = .{ .x = 0.4, .y = 8.8 } });+ try balls.append(.{ .pos = .{ .x = @as(f32, @floatFromInt(screenr.min.x + screenr.max.x)) / 2.0, .y = @as(f32, @floatFromInt(screenr.max.y)) }, .vel = .{ .x = -4.1, .y = 0.5 } }); while (true) {- try screen.draw(screen.r, d.white, null, ld.Point.Zero);
- ball.x += ballv.x;
- ball.y += ballv.y;
- if (ball.x > screenr.max.x or ball.x < screenr.min.x) {- ballv.x *= -1;
+ // clear the screen
+ try screen.draw(screen.r, d.white, null, Point.Zero);
+ // collide the balls
+ // update the balls
+ for (balls.items) |*ball| {+ ball.collide();
+ ball.pos.x += ball.vel.x;
+ ball.pos.y += ball.vel.y;
+ const p = ball.pos.toPoint();
+ if (p.x > screenr.max.x or p.x < screenr.min.x) {+ ball.vel.x *= -1;
+ }
+ if (p.y > screenr.max.y or p.y < screenr.min.y) {+ ball.vel.y *= -1;
+ }
}
- if (ball.y > screenr.max.y or ball.y < screenr.min.y) {- ballv.y *= -1;
- }
+ var quit = true;
+ // draw the squares
var i: u16 = 0;
- while (i < numsquares_vert) : (i += 1) {+ while (i < numbricks_vert) : (i += 1) {var j: u16 = 0;
- while (j < numsquares_horiz) : (j += 1) {- const square = squares[i * numsquares_vert + j];
- _ = square;
- var rect = ld.Rectangle.init(screenr.min.x + SQUARELEN * j, screenr.min.y + SQUARELEN * i, screenr.min.x + SQUARELEN * (j + 1) - SPACING, screenr.min.y + SQUARELEN * (i + 1) - SPACING);
- try screen.draw(rect, d.black, null, ld.Point.Zero);
+ while (j < numbricks_horiz) : (j += 1) {+ const square = bricks[i * numbricks_vert + j];
+ if (square > 0) {+ quit = false;
+ try screen.draw(getBrickRect(i, j), colors[square], null, Point.Zero);
+ }
}
}
- try screen.ellipse(ball, 10, 10, 10, d.black, ld.Point.Zero);
+ if (quit) break;
+ for (balls.items) |ball| {+ try screen.ellipse(ball.pos.toPoint(), 3, 3, 3, d.black, Point.Zero);
+ }
try d.flushImage(true);
_ = std.os.plan9.syscall_bits.syscall1(.SLEEP, 10);
}
--- a/src/libdraw.zig
+++ b/src/libdraw.zig
@@ -221,10 +221,10 @@
}
return true;
}
- pub fn dX(self: Rectangle) i64 {+ pub fn dX(self: Rectangle) i32 {return self.max.x - self.min.x;
}
- pub fn dY(self: Rectangle) i64 {+ pub fn dY(self: Rectangle) i32 {return self.max.y - self.min.y;
}
pub const width = dX;