Test Bresenham's algorithm

1 files changed, 33 insertions, 14 deletions

diff --git a/src/main.c b/src/main.c
index c179dc4..7f04f28 100644
--- a/src/main.c
+++ b/src/main.c
@@ -71,6 +71,10 @@ rgb15(u32 red, u32 green, u32 blue ) {
     return (blue << 10) | (green << 5) | red;
 }
 
+#define COLOR_RED  rgb15(31, 0, 12)
+#define COLOR_BLUE rgb15(2, 15, 30)
+#define COLOR_CYAN rgb15(0, 30, 30)
+
 // Using bd-font, an 8x8 bitmap font.
 static inline void
 put_char(int x, int y, Color clr, u8 chr) {
@@ -175,23 +179,38 @@ int main(void) {
     set_display_mode(DISP_MODE_3 | DISP_BG2);
 
 
-    put_text(0, 0, rgb15(18, 0, 0), "\n\n\n\n");
-
-    draw_line(0, 0, 3, 8,rgb15(0, 30, 0));
-    draw_line(8, 0, 16, 8,rgb15(0, 0, 30));
+    put_text(8, 8, COLOR_RED, "Testing Bresenham's algorithm");
 
-    draw_line(0, 0, 8, 3,rgb15(0, 0, 30));
-    draw_line(8, 0, 16, 8,rgb15(0, 0, 30));
-
-    // Testing a "rectangle"
-    draw_line(0, 0, 0, 7,rgb15(0, 0, 30));
-    draw_line(0, 0, 7, 0,rgb15(0, 30, 30));
-    draw_line(0, 7, 7, 7,rgb15(30, 0, 0));
-    draw_line(7, 0, 7, 7,rgb15(0, 30, 0));
+    for (size_t i = 70; i <= SCREEN_WIDTH - 70; i += 5) {
+        int x0 = i;
+        int y0 = 30;
+        int x1 = SCREEN_WIDTH - i;
+        int y1 = SCREEN_HEIGHT - 30;
+        draw_line(x0, y0, x1, y1, COLOR_BLUE);
+    }
+    for (size_t i = 30; i <= SCREEN_HEIGHT - 30; i += 5) {
+        int x0 = 70;
+        int y0 = i;
+        int x1 = SCREEN_WIDTH - 70;
+        int y1 = SCREEN_HEIGHT - i;
+        draw_line(x0, y0, x1, y1, COLOR_BLUE);
+    }
 
-    draw_line(8, 7, 15, 0,rgb15(0, 0, 30));
+    for (size_t i = 70; i <= SCREEN_WIDTH - 70; i += 10) {
+        int x0 = i;
+        int y0 = 30;
+        int x1 = SCREEN_WIDTH - i;
+        int y1 = SCREEN_HEIGHT - 30;
+        draw_line(x0, y0, x1, y1, COLOR_CYAN);
+    }
+    for (size_t i = 30; i <= SCREEN_HEIGHT - 30; i += 10) {
+        int x0 = 70;
+        int y0 = i;
+        int x1 = SCREEN_WIDTH - 70;
+        int y1 = SCREEN_HEIGHT - i;
+        draw_line(x0, y0, x1, y1, COLOR_CYAN);
+    }
 
-    char scanline_counter[16];
     while(true) {
         wait_vsync();
     };