Add Julia set example

2 files changed, 95 insertions, 22 deletions

diff --git a/examples/julia_set.c b/examples/julia_set.c
index 85a4674..9d12bb8 100755
--- a/examples/julia_set.c
+++ b/examples/julia_set.c
@@ -17,7 +17,7 @@ gcc                                         \
   -Wno-unused-but-set-variable              \
   -Wno-unused-parameter                     \
   -Wno-overlength-strings                   \
-  -O3                                       \
+  -g -O3                                    \
   -fsanitize=undefined,address,leak -mshstk \
   -lX11 -lm                                 \
   -o $BIN $SRC &&                           \
@@ -39,10 +39,70 @@ i32 main(i32 argc, c8 **argv) {
 
   p_init();
 
+  i64 p = 4;
+
+  f64 view_x = 0.;
+  f64 view_y = 0.;
+  f64 view_s = 1.;
+
+  f64 cx     = -.8;
+  f64 cy     = .1;
+  f64 radius = 2.;
+  i64 limit  = 1024;
+
   while (!platform.done) {
-    p_handle_events();
+    p_wait_events();
+
+    if (platform.key_pressed['\n'])
+      p = (p == 1 ? 4 : 1);
+
+    if (platform.key_pressed[KEY_ESCAPE]) {
+      view_x = 0.;
+      view_y = 0.;
+      view_s = 1.;
+    }
+
+    f64 d = platform.key_down[MOD_CTRL] ? .0005 : .01;
+
+    if (platform.key_pressed['q']) cx -= d;
+    if (platform.key_pressed['w']) cx += d;
+    if (platform.key_pressed['a']) cy -= d;
+    if (platform.key_pressed['s']) cy += d;
+
+
+    if (platform.key_down[BUTTON_LEFT]) {
+      view_x += platform.cursor_dx * view_s;
+      view_y += platform.cursor_dy * view_s;
+    }
+
+    view_s += .1 * platform.wheel_dy * view_s;
+
+    for (i32 j = 0; j + p <= platform.frame_height; j += p)
+      for (i32 i = 0; i + p <= platform.frame_width; i += p) {
+        f64 x = .003 * ((i - platform.frame_width  * .5) * view_s - view_x);
+        f64 y = .003 * ((j - platform.frame_height * .5) * view_s - view_y);
+
+        i64 n = 0;
+
+        for (; x * x + y * y < radius * radius && n < limit; ++n) {
+          f64 z = x * x - y * y;
+          y     = 2. * x * y  + cy;
+          x     = z + cx;
+        }
+
+        u32 c;
+
+        if (n == limit)
+          c = 0;
+        else
+          c = 0xffffff - n * 8 - n * 256 * 4;
+
+        for (i32 jj = 0; jj < p; ++jj)
+          for (i32 ii = 0; ii < p; ++ii)
+            platform.pixels[(j + jj) * platform.frame_width + (i + ii)] = c;
+      }
+
     p_render_frame();
-    p_sleep_for(0);
   }
 
   p_cleanup();
diff --git a/reduced_system_layer.c b/reduced_system_layer.c
index decd327..ffcec97 100755
--- a/reduced_system_layer.c
+++ b/reduced_system_layer.c
@@ -198,8 +198,6 @@ typedef struct {
   };
 } IP_Address;
 
-typedef i64 (*Thread_Proc)(void *user_data);
-
 //  UTF-8
 i32 utf8_size(c32 c);
 c32 utf8_read(i64 len, c8 *s);
@@ -626,6 +624,7 @@ i64 p_send(u16 slot, IP_Address address, i64 size, u8 *data, u16 *local_port) {
 #include <X11/Xatom.h>
 
 static i16       _key_table[512]                       = {0};
+static b8        _key_repeat[512]                      = {0};
 static u32       _buffer[MAX_NUM_PIXELS]               = {0};
 static Input_Key _input[MAX_INPUT_SIZE]                = {0};
 static c8        _clipboard_buffer[MAX_CLIPBOARD_SIZE] = {0};
@@ -757,6 +756,11 @@ void p_init(void) {
   i32 _display_width  = DisplayWidth (_display, screen);
   i32 _display_height = DisplayHeight(_display, screen);
 
+  if (platform.frame_width  <= 0)
+    platform.frame_width  = 400;
+  if (platform.frame_height <= 0)
+    platform.frame_height = 300;
+
   i32 x = (_display_width  - platform.frame_width)  / 2;
   i32 y = (_display_height - platform.frame_height) / 2;
 
@@ -804,6 +808,9 @@ void p_init(void) {
     XStoreName(_display, _window, platform.title);
 
   XMapWindow(_display, _window);
+
+  XPutImage(_display, _window, _gc, &_image, 0, 0, 0, 0, platform.frame_width, platform.frame_height);
+  XFlush(_display);
 }
 
 void p_cleanup(void) {
@@ -825,6 +832,7 @@ i32 p_handle_events(void) {
   i32 num_events = 0;
 
   memset(platform.key_pressed, 0, sizeof platform.key_pressed);
+  memset(_key_repeat, 0, sizeof _key_repeat);
 
   platform.input_size = 0;
   platform.cursor_dx  = 0;
@@ -858,16 +866,16 @@ i32 p_handle_events(void) {
         platform.cursor_y = ev.xbutton.y;
         switch (ev.xbutton.button) {
           case Button1:
-            platform.key_down[BUTTON_LEFT] = 1;
-            ++platform.key_pressed[BUTTON_LEFT];
+            platform.key_down[BUTTON_LEFT]    = 1;
+            platform.key_pressed[BUTTON_LEFT] = 1;
             break;
           case Button2:
-            platform.key_down[BUTTON_MIDDLE] = 1;
-            ++platform.key_pressed[BUTTON_MIDDLE];
+            platform.key_down[BUTTON_MIDDLE]    = 1;
+            platform.key_pressed[BUTTON_MIDDLE] = 1;
             break;
           case Button3:
-            platform.key_down[BUTTON_RIGHT] = 1;
-            ++platform.key_pressed[BUTTON_RIGHT];
+            platform.key_down[BUTTON_RIGHT]    = 1;
+            platform.key_pressed[BUTTON_RIGHT] = 1;
             break;
           case Button4: ++platform.wheel_dy; break;
           case Button5: --platform.wheel_dy; break;
@@ -894,14 +902,18 @@ i32 p_handle_events(void) {
         i16 k = _key_table[ev.xkey.keycode];
         platform.cursor_x = ev.xkey.x;
         platform.cursor_y = ev.xkey.y;
-        platform.key_down   [k] = 1;
-        platform.key_pressed[k]++;
+
+        platform.key_down[k] = 1;
+        if (!_key_repeat[k])
+          platform.key_pressed[k] = 1;
+
         platform.key_down[MOD_CTRL]   = !!(ev.xkey.state & ControlMask);
         platform.key_down[MOD_SHIFT]  = !!(ev.xkey.state & ShiftMask);
         platform.key_down[MOD_ALT]    = !!(ev.xkey.state & Mod1Mask);
         platform.key_down[MOD_CAPS]   = !!(ev.xkey.state & LockMask);
         platform.key_down[MOD_NUM]    = !!(ev.xkey.state & Mod2Mask);
         platform.key_down[MOD_SCROLL] = !!(ev.xkey.state & Mod3Mask);
+
         if (platform.input_size < MAX_INPUT_SIZE) {
           if (k < 32 || k >= 128)
             platform.input[platform.input_size++] = (Input_Key) {
@@ -930,6 +942,7 @@ i32 p_handle_events(void) {
               };
           }
         }
+
         if (!requested_clipboard) {
           XConvertSelection(_display, _clipboard, _targets, _clipboard, _window, CurrentTime);
           requested_clipboard = 1;
@@ -938,10 +951,13 @@ i32 p_handle_events(void) {
 
       case KeyRelease: {
         i16 k = _key_table[ev.xkey.keycode];
+
         platform.cursor_x = ev.xkey.x;
         platform.cursor_y = ev.xkey.y;
-        platform.key_down   [k] = 0;
-        platform.key_pressed[k]--;
+
+        platform.key_down[k] = 0;
+        _key_repeat[k]       = 1;
+
         platform.key_down[MOD_CTRL]   = !!(ev.xkey.state & ControlMask);
         platform.key_down[MOD_SHIFT]  = !!(ev.xkey.state & ShiftMask);
         platform.key_down[MOD_ALT]    = !!(ev.xkey.state & Mod1Mask);
@@ -995,15 +1011,15 @@ i32 p_handle_events(void) {
 
       case SelectionNotify:
         if (ev.xselection.property != None) {
-          i64 len;
-          u8 *data;
+          i64 len  = 0;
+          u8 *data = NULL;
 
           XGetWindowProperty(
             _display,
             _window,
             _clipboard,
             0,
-            MAX_CLIPBOARD_SIZE,
+            MAX_CLIPBOARD_SIZE / 4,
             False,
             AnyPropertyType,
             &(Atom) {0},
@@ -1017,7 +1033,7 @@ i32 p_handle_events(void) {
             _target    = None;
             Atom *list = (Atom *) data;
 
-            for (i64 i = 0; i < len; i++)
+            for (i64 i = 0; i < len / 4; i++)
               if (list[i] == XA_STRING)
                 _target = XA_STRING;
               else if (list[i] == _utf8_string) {
@@ -1065,9 +1081,6 @@ i32 p_handle_events(void) {
     }
   }
 
-  for (i64 k = 0; k < (i64) (sizeof platform.key_pressed / sizeof *platform.key_pressed); ++k)
-    platform.key_pressed[k] = platform.key_pressed[k] > 0 ? 1 : 0;
-
   XWindowAttributes attrs;
   XGetWindowAttributes(_display, _window, &attrs);