Some line drawing functions

src/libmittos/graphics/graphics.c

@@ -17,6 +17,43 @@ void putpixel(gfx_context *ctx, uint64_t x, uint64_t y, uint32_t clr)
     *fb = clr;
 }
 
+void draw_line(gfx_context *ctx, uint64_t x0, uint64_t x1, uint64_t y0, uint64_t y1, uint32_t clr)
+{
+    int64_t dx = x1 > x0 ? x1 - x0 : x0 - x1;
+    int64_t dy = y1 > y0 ? y1 - y0 : y0 - y1;
+    int sx = x1 > x0 ? 1 : -1;
+    int sy = y1 > y0 ? 1 : -1;
+    uint64_t x = x0, y = y0;
+    int64_t diff = dx - dy;
+    while(1)
+    {
+        putpixel(ctx, x, y, clr);
+        if(x == x1 && y == y1) break;
+        
+        if((2*diff) > -dy) {
+            diff -= dy;
+            x += sx;
+        } else {
+            diff += dx;
+            y += sy;
+        }
+    }
+}
+
+void draw_rect(gfx_context *ctx, uint64_t x, uint64_t y, uint64_t width, uint64_t height, uint32_t clr)
+{
+    for(uint64_t _x = x; _x <= x+width; _x++)
+    {
+        putpixel(ctx, _x, y, clr);
+        putpixel(ctx, _x, y+height, clr);
+    }
+    for(uint64_t _y = y; _y <= y+height; _y++)
+    {
+        putpixel(ctx, x, _y, clr);
+        putpixel(ctx, x+width, _y, clr);
+    }
+}
+
 void putCharacter(gfx_context *ctx, uint64_t x, uint64_t y, uint32_t clr_fg, uint32_t clr_bg, char c)
 {
 

src/libmittos/include/graphics.h

@@ -14,6 +14,8 @@ typedef struct {
 #define RGB(r, g, b) (((uint32_t) (r<<16) + (g<<8) + (b)))
 
 void putpixel(gfx_context *ctx, uint64_t x, uint64_t y, uint32_t clr);
+void draw_line(gfx_context *ctx, uint64_t x0, uint64_t x1, uint64_t y0, uint64_t y1, uint32_t clr);
+void draw_rect(gfx_context *ctx, uint64_t x, uint64_t y, uint64_t width, uint64_t height, uint32_t clr);
 void putCharacter(gfx_context *ctx, uint64_t x, uint64_t y, uint32_t clr_fg, uint32_t clr_bg, char c);
 void flip(gfx_context *ctx);
 gfx_context *framebuffer_make_subcontext(gfx_context *ctx, uint64_t x, uint64_t y, uint64_t width, uint64_t height);