From 93ce68f527d1d90d60ee5b49fa78ef17f672a9e4 Mon Sep 17 00:00:00 2001
From: jonathan santis <jonathan.wyss@santismail.ch>
Date: Thu, 24 Oct 2024 09:28:12 +0200
Subject: [PATCH] bresenham done

---
 main.zig | 28 +++++++++++++++++++++-------
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/main.zig b/main.zig
index 69775b7..9f0698d 100644
--- a/main.zig
+++ b/main.zig
@@ -144,6 +144,8 @@ fn fillBuffer() !void {
     _ = try bresenham(buffer, w, Point{ .x = 60, .y = 30, .z = 0 }, Point{ .x = 70, .y = 5, .z = 0 });
     _ = try bresenham(buffer, w, Point{ .x = 100, .y = 20, .z = 0 }, Point{ .x = 30, .y = 30, .z = 0 });
     _ = try bresenham(buffer, w, Point{ .x = 100, .y = 10, .z = 0 }, Point{ .x = 90, .y = 40, .z = 0 });
+    _ = try bresenham(buffer, w, Point{ .x = 100, .y = 30, .z = 0 }, Point{ .x = 90, .y = 10, .z = 0 });
+    _ = try bresenham(buffer, w, Point{ .x = 100, .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 {
@@ -162,12 +164,11 @@ fn bresenham(buf: []u8, w: Winsize, p1: Point, p2: Point) !void {
     //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 dy = (p2.y - p1.y);
     //const slope = dx/dy;
     var er: i64 = 0;
     if (dx >= dy and dy > 0 and dx > 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) {
@@ -177,7 +178,6 @@ fn bresenham(buf: []u8, w: Winsize, p1: Point, p2: Point) !void {
         }
     } else if (dx < dy and dy > 0 and dx > 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) {
@@ -187,7 +187,6 @@ fn bresenham(buf: []u8, w: Winsize, p1: Point, p2: Point) !void {
         }
     } else if (@abs(dy) < dx and dy < 0 and dx > 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, '🡇');
             er -= dy;
             if (2 * er >= dx) {
@@ -197,7 +196,6 @@ fn bresenham(buf: []u8, w: Winsize, p1: Point, p2: Point) !void {
         }
     } else if (@abs(dy) > dx and dy < 0 and dx > 0) {
         while (y >= p2.y) : (y -= 1) {
-            print("[bresenham4]x:{},y:{},er:{},dx:{},dy:{}\n", .{ x, y, er, dx, dy });
             _ = try pixel(buf, w, x, y, '=');
             er += dx;
             if (2 * er >= dy) {
@@ -207,7 +205,6 @@ fn bresenham(buf: []u8, w: Winsize, p1: Point, p2: Point) !void {
         }
     } else if (@abs(dx) <= dy and dx < 0 and dy > 0) {
         while (y <= p2.y) : (y += 1) {
-            print("[bresenham5]x:{},y:{},er:{},dx:{},dy:{}\n", .{ x, y, er, dx, dy });
             _ = try pixel(buf, w, x, y, '5');
             er += @abs(dx);
             if (2 * er >= dy) {
@@ -217,7 +214,6 @@ fn bresenham(buf: []u8, w: Winsize, p1: Point, p2: Point) !void {
         }
     } else if (@abs(dx) > dy and dy > 0 and dx < 0) {
         while (x >= p2.x) : (x -= 1) {
-            print("[bresenham6]x:{},y:{},er:{},dx:{},dy:{}\n", .{ x, y, er, dx, dy });
             _ = try pixel(buf, w, x, y, '6');
             er += dy;
             if (2 * er >= @abs(dx)) {
@@ -225,6 +221,24 @@ fn bresenham(buf: []u8, w: Winsize, p1: Point, p2: Point) !void {
                 er -= @abs(dx);
             }
         }
+    } else if (dx <= dy and dx < 0 and dy < 0) {
+        while (x >= p2.x) : (x -= 1) {
+            _ = try pixel(buf, w, x, y, '7');
+            er += @abs(dy);
+            if (2 * er >= @abs(dx)) {
+                y -= 1;
+                er -= @abs(dx);
+            }
+        }
+    } else if (dx > dy and dy < 0 and dx < 0) {
+        while (y >= p2.y) : (y -= 1) {
+            _ = try pixel(buf, w, x, y, '8');
+            er += @abs(dx);
+            if (2 * er >= @abs(dx)) {
+                x -= 1;
+                er -= @abs(dx);
+            }
+        }
     }
 }