cool bug

5 files changed, 59 insertions, 1 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 28424ad..19bb98b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,6 +10,8 @@ include(Fxconv)
 find_package(Gint 2.9 REQUIRED)
 
 set(SOURCES
+  src/background.c
+  src/entity.c
   src/game.c
   src/lzy.c
   src/main.c
diff --git a/build.sh b/build.sh
index 3501041..149511a 100755
--- a/build.sh
+++ b/build.sh
@@ -1,2 +1,3 @@
 #!/bin/sh
-gcc -std=c99 -Wall -Wextra -o hyperultra src/*.c -lSDL2 -lSDL2_image -lSDL2_mixer
+gcc -std=c99 -Wall -Wextra -o hyperultra src/*.c \
+    -lm -lSDL2 -lSDL2_image -lSDL2_mixer
diff --git a/src/background.c b/src/background.c
new file mode 100644
index 0000000..2b32c49
--- /dev/null
+++ b/src/background.c
@@ -0,0 +1,50 @@
+#include "lzy.h"
+#include "cfg.h"
+#include <math.h>
+
+static long tick = 0;
+static const int center_x = DISPLAY_WIDTH / 2;
+static const int center_y = DISPLAY_HEIGHT / 2;
+
+static void
+rotate(double *x, double *y, double angle)
+{
+	const int ox = *x;
+	*x = *x * cos(angle) + *y * sin(angle);
+	*y = *y * cos(angle) + ox * sin(angle);
+}
+
+static void
+draw_square(int size, double angle)
+{
+	double x0 = size / 2.0;
+	double y0 = size / 2.0;
+	double x1 = size / 2.0;
+	double y1 = -size / 2.0;
+	rotate(&x0, &y0, angle);
+	rotate(&x1, &y1, angle);
+	double x2 = 0 - x0;
+	double y2 = 0 - y0;
+	double x3 = 0 - x0;
+	double y3 = 0 - y0;
+	x0 += center_x;
+	y0 += center_y;
+	x1 += center_x;
+	y1 += center_y;
+	x2 += center_x;
+	y2 += center_y;
+	x3 += center_x;
+	y3 += center_y;
+	LZY_DrawLine(x0, y0, x1, y1);
+	LZY_DrawLine(x1, y1, x2, y2);
+	LZY_DrawLine(x2, y2, x3, y3);
+	LZY_DrawLine(x3, y3, x0, y0);
+}
+
+void
+background_draw(void)
+{
+	tick += 1;
+	LZY_DrawSetColor(0, 0, 0);
+	draw_square(tick % 128, (double)tick / 10);
+}
diff --git a/src/background.h b/src/background.h
new file mode 100644
index 0000000..def5923
--- /dev/null
+++ b/src/background.h
@@ -0,0 +1,3 @@
+#pragma once
+
+void background_draw(void);
diff --git a/src/main.c b/src/main.c
index 1f7f7c1..f03fffa 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,6 +1,7 @@
 #include "lzy.h"
 #include "game.h"
 #include "player.h"
+#include "background.h"
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -28,6 +29,7 @@ int main(void)
 		LZY_DrawBegin();
 		LZY_DrawSetColor(255, 255, 255);
 		LZY_DrawClear();
+		background_draw();
 		game_draw(game);
 		LZY_DrawEnd();
 	}