Create approximating_pi.c

examples/approximating_pi.c

@@ -0,0 +1,60 @@
+#define CGL_EXCLUDE_NETWORKING
+#define CGL_LOGGING_ENABLED
+#define CGL_IMPLEMENTATION
+#include "cgl.h"
+
+static struct
+{
+    CGL_window* window; // the main window
+    CGL_int window_height;
+    CGL_int window_width;
+    CGL_framebuffer* framebuffer;
+} g_context;
+
+int main()
+{
+    srand((uint32_t)time(NULL));
+    if(!CGL_init()) return EXIT_FAILURE; // initialize CGL (required for setting up internals of CGL)
+    g_context.window_height = g_context.window_width = 700;
+    g_context.window = CGL_window_create(g_context.window_width, g_context.window_height, "Approximating PI - Jaysmito Mukherjee"); // create the window
+    CGL_window_make_context_current(g_context.window); // make the opengl context for the window current
+    if(!CGL_gl_init()) return EXIT_FAILURE; // initialize cgl opengl module    
+    g_context.framebuffer = CGL_framebuffer_create_from_default(g_context.window); // load the default framebuffer (0) into CGL_framebuffer object
+    if(!CGL_widgets_init()) return EXIT_FAILURE; 
+    CGL_float prev_time = CGL_utils_get_time(), curr_time = 0.0f, delta_time = 0.0f, frame_time = 0.0f;
+    CGL_int frame_count = 0, frame_rate = 60; CGL_float point_size = 0.01f;
+    CGL_double points_in_square = 1.0, points_in_circle = 1.0, pi_value = 0.0;
+    CGL_vec2 min_val = CGL_vec2_init(-1.0f, -1.0f), max_val = CGL_vec2_init(1.0f, 1.0f), curr_val;
+    // the main loop
+    while(!CGL_window_should_close(g_context.window)) // run till the close button is clicked
+    {
+        curr_time = CGL_utils_get_time();
+        delta_time = curr_time - prev_time; prev_time = curr_time; frame_time += delta_time; frame_count++;
+        if(frame_time >= 1.0f) { frame_rate = frame_count; frame_time = 0.0f; frame_count = 0; }
+        CGL_window_set_size(g_context.window, g_context.window_width, g_context.window_height); // set the window size
+        CGL_framebuffer_bind(g_context.framebuffer); // bind default framebuffer and also adjust viewport size and offset
+        CGL_widgets_begin();
+        curr_val = CGL_utils_random_vec2(min_val, max_val);
+        if(CGL_vec2_length(curr_val) <= 1.0) { points_in_circle += 1.0; CGL_widgets_set_fill_colorf(0.0f, 0.8f, 0.0f, 1.0f);}
+        else CGL_widgets_set_fill_colorf(0.0f, 0.0f, 0.8f, 1.0f); points_in_square += 1.0; 
+        pi_value = 4.0 * (points_in_circle / points_in_square);
+        CGL_widgets_add_rect2f(curr_val.x, curr_val.y, point_size, point_size);
+        CGL_widgets_set_fill_colorf(0.0f, 0.0f, 0.0f, 1.0f);
+        CGL_widgets_add_rect2f(-0.3f, -0.1f, 0.6f, 0.2f);
+        CGL_widgets_set_fill_colorf(0.7f, 0.7f, 0.7f, 1.0f);
+        static CGL_byte buffer[256]; sprintf(buffer, "%lf", pi_value);
+        CGL_widgets_add_string(buffer, -0.3f, -0.1f, 0.6f, 0.2f);
+        CGL_widgets_end();
+        if(CGL_window_is_key_pressed(g_context.window, CGL_KEY_SPACE)) {CGL_gl_clear(0.0f, 0.0f, 0.0f, 1.0f); points_in_circle = 1.0; points_in_square = 1.0;}
+        CGL_window_swap_buffers(g_context.window); // swap framebuffers
+        CGL_window_poll_events(g_context.window); // poll events (if this is not called every frame window will stop responding)
+        if(CGL_window_get_key(g_context.window, CGL_KEY_ESCAPE) == CGL_PRESS) break; // quit on pressing escape
+    }
+    // cleanup
+    CGL_widgets_shutdown();
+    CGL_framebuffer_destroy(g_context.framebuffer); // destory framebuffer object
+    CGL_gl_shutdown(); // shutdown cgl opengl module
+    CGL_window_destroy(g_context.window); // destroy window
+    CGL_shutdown(); // shutdown cgl and clean up resources allocated by CGL internally (if any)
+    return EXIT_SUCCESS;
+}