From 0b4239a67997f3450f60144ac19fb51a8bb0c957 Mon Sep 17 00:00:00 2001
From: jonathan santis <jonathan.wyss@santismail.ch>
Date: Tue, 22 Oct 2024 12:59:47 +0200
Subject: [PATCH] sdf

---
 main.zig | 144 +++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 129 insertions(+), 15 deletions(-)

diff --git a/main.zig b/main.zig
index 00ec4a1..2c80c58 100644
--- a/main.zig
+++ b/main.zig
@@ -2,27 +2,64 @@ 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: u32,
+    y: u32,
+    z: u32,
+};
+const Vec3 = struct {
+    a: Point,
+    b: Point,
+    c: Point,
+};
 
 pub fn main() !void {
-    //const buffer: [:0]u8 = undefined;
-    std.debug.print("Hello, {s}\n", .{"World"});
+    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| {
-        const buffer = buf;
-        _ = buffer;
         print("Buffer:{s}\n", .{buf});
-
-        const slice = getNum("123dsfi843w653487 38745 631875 61385631856__87234982374924__auf_123_45t63sadf9875,231,1");
-        //_ = slice;
-        //print("number1: {d}", .{slice[0]});
-        for (slice) |num| {
-            print("extracted number:\n{d}\n", .{num});
-        }
+        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;
@@ -57,12 +94,12 @@ fn getNum(str1: []const u8) []u64 {
     return &num_res;
 }
 fn createFile() !void {
-    const file = try std.fs.cwd().openFile("junk-file.txt", .{});
+    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) });
+    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);
@@ -74,3 +111,80 @@ fn createFile() !void {
         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 = 40, .z = 0 }, Point{ .x = 100, .y = 20, .z = 0 });
+    try file.writeAll(buffer);
+}
+fn pixel(buffer: []u8, w: Winsize, x: u64, y: u64, symbol: u21) !void {
+    const i = 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: u64 = p1.x;
+    var y: u64 = p1.y;
+    const dx = (p2.x - p1.x);
+    const a: u32 = 20;
+    const b: u32 = 40;
+    var c1: i64 = 0;
+    c1 = a - b;
+    print("c:{}\n", .{c1});
+    print("p2: {} - {},{}", .{ p2.y, p1.y, p2.y - p1.y });
+    var dy: i64 = ((p2.y) - (p1.y));
+    //const slope = dx/dy;
+    var er: i64 = 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, '.');
+
+        if (dy > 0) {
+            er += dy;
+            if (2 * er >= dx) {
+                y += 1;
+                er -= dx;
+            }
+        } else if (dy < 0) {
+            er -= dy;
+            if (2 * er >= dx) {
+                y -= 1;
+                er += dx;
+            }
+        }
+    }
+    dy = 0;
+}
+
+//fn triangle(vec: Vec3) void {
+
+//}