1 files changed, 124 insertions, 0 deletions
diff --git a/circle-thingy/main.c b/circle-thingy/main.c
new file mode 100644
index 0000000..38ba0fb
--- /dev/null
+++ b/circle-thingy/main.c
@@ -0,0 +1,124 @@
+#include <stdio.h>
+#include <stdbool.h>
+
+#ifdef PLATFORM_WEB
+  #include RAYLIB_SRC
+#else
+  #include <raylib.h>
+#endif
+
+// game coords to screen coords
+#define GTOS(n) ((n) * (SH) / 2)
+#define GTOSV(n) ((Vector2){(GTOS(n.x)), (GTOS(n.y))})
+// screen coords to game coords
+#define STOG(n) ((n) / (SH) * 2)
+#define STOGV(n) ((Vector2){(STOG(n.x)), (STOG(n.y))})
+
+#define IN_RANGE(x, y, z) (((x) > ((y) - (z))) && ((x) < ((y) + (z))))
+#define IN_RANGEV(a, b, c) ((IN_RANGE(a.x, b.x, c)) && (IN_RANGE(a.y, b.y, c)))
+
+int SW = 1200;
+int SH =  800;
+int MAX_ITER = 50;
+
+Vector2 a = {-1, 0};
+Vector2 b = { 1, 0};
+
+char text[1024];
+
+Vector2 median(Vector2 p1, Vector2 p2)
+{
+    return (Vector2){(p1.x + p2.x)/2, (p1.y + p2.y)/2};
+}
+
+void calc_points(Vector2 p1, Vector2 p2, Vector2 q)
+{
+    static int iter = 0;
+    if(iter++ >= MAX_ITER) {
+        sprintf(text, "iter: %d; x: %f; y: %f", iter-1, p1.x, -p1.y);
+        iter = 0;
+        return;
+    }
+
+    DrawLineV(GTOSV(p1), GTOSV(p2), (iter % 2 == 0) ? RED : BLUE);
+
+    calc_points(q, median(p1, p2), p2);
+}
+
+int main(void)
+{
+    InitWindow(SW, SH, "circle thingy");
+    SetTargetFPS(60);
+    SetWindowState(FLAG_WINDOW_RESIZABLE);
+
+    printf("\n----------------------- Instructions -----------------------\n");
+    printf("Use WASD to move around\n");
+    printf("Use Q and E increase or decrease the iterations\n");
+    printf("Use the mouse to move the points and to zoom in or out\n");
+    printf("------------------------------------------------------------\n");
+
+    Camera2D camera = {0};
+    camera.zoom = 1.0f;
+
+    while (!WindowShouldClose())
+    {
+        // for resizing
+        SW = GetScreenWidth();
+        SH = GetScreenHeight();
+        camera.offset = (Vector2){SW/2.0f, SH/2.0f};
+
+        if(IsKeyDown(KEY_W)) camera.target.y -= 500.0f * GetFrameTime();
+        if(IsKeyDown(KEY_A)) camera.target.x -= 500.0f * GetFrameTime();
+        if(IsKeyDown(KEY_S)) camera.target.y += 500.0f * GetFrameTime();
+        if(IsKeyDown(KEY_D)) camera.target.x += 500.0f * GetFrameTime();
+        if(IsKeyPressed(KEY_Q)) MAX_ITER++;
+        if(IsKeyPressed(KEY_E)) MAX_ITER--;
+        camera.zoom += ((float)GetMouseWheelMove()*0.05f);
+
+        static bool a_moving = false;
+        static bool b_moving = false;
+
+        BeginDrawing();
+        ClearBackground(RAYWHITE);
+
+        BeginMode2D(camera);
+            DrawCircleLines(0, 0, GTOS(1), BLACK);
+            DrawLine(GTOS(0), GTOS(1), GTOS(0), GTOS(-1), BLACK);
+            DrawLine(GTOS(1), GTOS(0), GTOS(-1), GTOS(0), BLACK);
+
+            DrawCircleV(GTOSV(a), 10, BLUE);
+            DrawCircleV(GTOSV(b), 10, RED);
+
+            // moving the point a
+            if(IN_RANGEV(GetScreenToWorld2D(GetMousePosition(), camera), GTOSV(a), 10)
+               || a_moving) {
+                DrawCircleLines(GTOS(a.x), GTOS(a.y), 13, BLUE);
+
+                if(IsMouseButtonDown(MOUSE_BUTTON_LEFT) && !b_moving) {
+                    a = STOGV(GetScreenToWorld2D(GetMousePosition(), camera));
+                    a_moving = true;
+                } else a_moving = false;
+            }
+
+            // moving the point b
+            if(IN_RANGEV(GetScreenToWorld2D(GetMousePosition(), camera), GTOSV(b), 10)
+               || b_moving) {
+                DrawCircleLines(GTOS(b.x), GTOS(b.y), 13, RED);
+
+                if(IsMouseButtonDown(MOUSE_BUTTON_LEFT) && !a_moving) {
+                    b = STOGV(GetScreenToWorld2D(GetMousePosition(), camera));
+                    b_moving = true;
+                } else b_moving = false;
+            }
+
+            calc_points((Vector2){0, -1}, a, b);
+        EndMode2D();
+
+        DrawFPS(10, 10);
+        DrawText(text, 100, 10, 30, DARKGREEN);
+        EndDrawing();
+    }
+
+    CloseWindow();
+    return 0;
+}