zig-learn/main.zig
2024-10-23 13:51:33 +02:00

204 lines
6.4 KiB
Zig

const std = @import("std");
const expect = std.testing.expect;
const print = std.debug.print;
const getenv = std.posix.getenv;
const ioctl = std.c.ioctl;
const c = @cImport({
@cDefine("_NO_CRT_STDIO_INLINE", "1");
@cInclude("sys/ioctl.h");
@cInclude("stdio.h");
});
const Winsize = struct {
ws_row: c_ushort = 0,
ws_col: c_ushort = 0,
ws_xpixel: c_ushort = 0,
ws_ypixel: c_ushort = 0,
};
const Point = struct {
x: i32,
y: i32,
z: i32,
};
const Vec3 = struct {
a: Point,
b: Point,
c: Point,
};
pub fn main() !void {
var win = Winsize{};
win = try getTermDimension();
print("winsize.ws_row: {}\nws_line: {}\nws_xpixel: {} \nws_ypixel: {}\n", .{ win.ws_row, win.ws_col, win.ws_xpixel, win.ws_ypixel });
try fillBuffer();
try createFile();
if (getenv("TERM")) |buf| {
print("Buffer:{s}\n", .{buf});
const slice = getNum(buf);
_ = slice;
//for (slice) |num| {
// print("extracted number:\n{d}\n", .{num});
//}
} else {
print("Error getenv\n", .{});
}
}
fn getTermDimension() !Winsize {
var w = Winsize{};
var ret: u16 = 0;
const err = error{CUnknown};
//print("stdout_fileno: {}\n", .{@TypeOf(std.c.STDOUT_FILENO)});
ret = @intCast(ioctl(std.c.STDOUT_FILENO, c.TIOCGWINSZ, &w));
if (ret > 0) {
return err.CUnknown;
}
//print("winsize.ws_row: {}\nws_line: {}\nws_xpixel: {} \nws_ypixel: {}\n", .{ w.ws_row, w.ws_col, w.ws_xpixel, w.ws_ypixel });
return w;
}
fn getNum(str1: []const u8) []u64 {
//_ = str1;
var pos: u64 = 0;
var num = std.mem.zeroes([64]u64);
var num_res = std.mem.zeroes([16]u64);
var it: u64 = 0;
for (str1, 0..) |elem, it2| {
if (elem >= 48 and elem <= 57) { //is ascii number?
num[pos] = @intCast(elem - 48);
if (pos <= @bitSizeOf(@TypeOf(pos))) {
pos += 1;
} else {
print("ERROR int u64 oveflow! pos {d} ,max {d}\n", .{ pos, @bitSizeOf(@TypeOf(pos)) });
}
}
//Calculate int out of characters
if ((elem < 48 or elem > 57) or it2 == (str1.len - 1)) {
if (pos != 0) {
for (0..pos) |i| {
if (i < pos - 1) {
num_res[it] = num_res[it] + num[i] * (std.math.pow(u64, 10, (pos - i - 1)));
} else {
num_res[it] = num_res[it] + num[i];
}
}
//print("numres:{}={}\n", .{ it, num_res[it] });
pos = 0;
it += 1;
}
}
}
return &num_res;
}
fn createFile() !void {
const file = try std.fs.cwd().openFile("junk-file.txt", .{ .mode = std.fs.File.OpenMode.read_write });
defer file.close();
const bytes_written = try file.writeAll("hello world!");
//_ = bytes_written;
std.debug.print("files written:{any}, {any}", .{ bytes_written, @TypeOf(bytes_written) });
var buffer: [100]u8 = undefined;
try file.seekTo(0);
const bytes_read = try file.readAll(&buffer);
print("buffer: {s} check: {s}\n", .{ buffer[0..bytes_read], "hello world!" });
if (std.mem.eql(u8, buffer[0 .. bytes_read - 1], "hello world!") == true) {
print("equal\n", .{});
} else {
print("not equal\n", .{});
}
}
fn fillBuffer() !void {
const allocator = std.heap.page_allocator;
var w = Winsize{};
var i: u64 = 0;
w = try getTermDimension();
const file = try std.fs.cwd().createFile("buffer.out", .{});
defer file.close();
var buffer = try allocator.alloc(u8, w.ws_row * w.ws_col * 4); //utf-8 can be 4 bytes long
defer allocator.free(buffer);
buffer[0] = 0;
while (i < buffer.len) : (i += 4) {
const slice = buffer[i .. i + 4];
_ = try std.unicode.utf8Encode('\u{2588}', slice);
}
try pixel(buffer, w, 5, 10, '\u{1F702}');
const vec = Vec3{
.a = Point{ .x = 0, .y = 1, .z = 2 },
.b = Point{ .x = 0, .y = 1, .z = 20 },
.c = Point{ .x = 0, .y = 1, .z = 2 },
};
_ = vec;
//triangle(vec);
_ = try bresenham(buffer, w, Point{ .x = 10, .y = 10, .z = 0 }, Point{ .x = 30, .y = 12, .z = 0 });
_ = try bresenham(buffer, w, Point{ .x = 10, .y = 10, .z = 0 }, Point{ .x = 30, .y = 28, .z = 0 });
_ = try bresenham(buffer, w, Point{ .x = 10, .y = 10, .z = 0 }, Point{ .x = 30, .y = 30, .z = 0 });
_ = try bresenham(buffer, w, Point{ .x = 10, .y = 10, .z = 0 }, Point{ .x = 30, .y = 40, .z = 0 });
_ = try bresenham(buffer, w, Point{ .x = 30, .y = 30, .z = 0 }, Point{ .x = 60, .y = 10, .z = 0 });
try file.writeAll(buffer);
}
fn pixel(buffer: []u8, w: Winsize, x: i64, y: i64, symbol: u21) !void {
const i: usize = @intCast(4 * (x + y * w.ws_col));
if (i < buffer.len) {
const slice = buffer[i .. i + 4];
print("slice:{u}\n", .{slice});
_ = try std.unicode.utf8Encode(symbol, slice);
print("slice after:{u}\n", .{slice});
print("cols{}\ni: {}\n", .{ w.ws_col, i });
} else {
print("Error illegal memory access\n", .{});
}
}
fn bresenham(buf: []u8, w: Winsize, p1: Point, p2: Point) !void {
var x: i32 = p1.x;
var y: i32 = p1.y;
//var x: i32 = 0;
//var y: i32 = 0;
const dx = (p2.x - p1.x);
print("p2: {} - {},{}\n", .{ p2.y, p1.y, p2.y - p1.y });
const dy: i64 = (p2.y - p1.y);
//const slope = dx/dy;
var er: i64 = 0;
if (dx >= dy and dy > 0) {
while (x <= p2.x) : (x += 1) {
print("[bresenham]x:{},y:{},er:{},dx:{},dy:{}\n", .{ x, y, er, dx, dy });
_ = try pixel(buf, w, x, y, '.');
er += dy;
if (2 * er >= dx) {
y += 1;
er -= dx;
}
}
} else if (dx < dy and dy > 0) {
while (y <= p2.y) : (y += 1) {
print("[bresenham2]x:{},y:{},er:{},dx:{},dy:{}\n", .{ x, y, er, dx, dy });
_ = try pixel(buf, w, x, y, ',');
er += dx;
if (2 * er >= dy) {
x += 1;
er -= dy;
}
}
} else if (@abs(dy) < dx and dy < 0) {
while (x <= p2.x) : (x += 1) {
print("[bresenham3]x:{},y:{},er:{},dx:{},dy:{}\n", .{ x, y, er, dx, dy });
_ = try pixel(buf, w, x, y, 'x');
er -= dy;
if (2 * er >= dx) {
y -= 1;
er -= dx;
}
}
}
}
//fn triangle(vec: Vec3) void {
//}