Refactor

3 files changed, 62 insertions, 64 deletions

diff --git a/graphics.c b/graphics.c
index ea7edee..1650d32 100644
--- a/graphics.c
+++ b/graphics.c
@@ -309,12 +309,14 @@ void draw_pixels_(Brush brush, f64 x, f64 y, f64 width, f64 height, Pixel_Buffer
     for (i64 j = j0; j <= j1; ++j) {
       i64 src_j0 = (i64) floor(((j     - y0) * src.height) / h + .5);
       i64 src_j1 = (i64) floor(((j + 1 - y0) * src.height) / h + .5);
+      if (src_j0 == src_j1) src_j1 = src_j0 + 1;
       if (src_j1 <= 0 || src_j0 >= src.height) continue;
       if (src_j0 < 0)          src_j0 = 0;
       if (src_j1 > src.height) src_j1 = src.height;
       for (i64 i = i0; i <= i1; ++i) {
         i64 src_i0 = (i64) floor(((i     - x0) * src.width) / w + .5);
         i64 src_i1 = (i64) floor(((i + 1 - x0) * src.width) / w + .5);
+        if (src_i0 == src_i1) src_i1 = src_i0 + 1;
         if (src_i1 <= 0 || src_i0 >= src.width) continue;
         if (src_i0 < 0)         src_i0 = 0;
         if (src_i1 > src.width) src_i1 = src.width;
diff --git a/index.htm b/index.htm
index ada10e2..18c110f 100644
--- a/index.htm
+++ b/index.htm
@@ -47,6 +47,7 @@
 
                       floor : Math.floor,
                       ceil  : Math.ceil,
+                      trunc : Math.trunc,
                       sqrt  : Math.sqrt,
                       cbrt  : Math.cbrt,
                       pow   : Math.pow,
diff --git a/reduced_system_layer.c b/reduced_system_layer.c
index b7f5954..6032ee3 100644
--- a/reduced_system_layer.c
+++ b/reduced_system_layer.c
@@ -225,6 +225,8 @@ i32 main(i32 argc, c8 **argv);
 
 #ifndef AVERAGE_FRAME_BIAS
 #if defined(__wasm__)
+//  NOTE: Web frame rate is quite unstable, so
+//        we always pick the longest frame.
 #define AVERAGE_FRAME_BIAS (0.00)
 #else
 #define AVERAGE_FRAME_BIAS (0.02)
@@ -280,6 +282,7 @@ i32 main(i32 argc, c8 **argv);
 #else
 f64 floor(f64 x);
 f64 ceil(f64 x);
+f64 trunc(f64 x);
 f64 sqrt(f64 x);
 f64 cbrt(f64 x);
 f64 pow(f64 x, f64 y);
@@ -753,10 +756,17 @@ static i64 average_frame_duration_(i64 duration) {
   for (i64 i = 0; i < NUM_FRAMES_AVERAGED; ++i)
     durs[i] = _frame_duration[i];
 
-  //  FIXME: Use better sorting algorithm.
+  //  FIXME: Use better sorting algorithm, e.g. merge sort.
   for (i64 i = 0; i < (i64) NUM_FRAMES_AVERAGED; ++i)
     for (i64 j = i + 1; j < NUM_FRAMES_AVERAGED; ++j)
-      if (durs[i] < durs[j]) { i64 t = durs[i]; durs[i] = durs[j]; durs[j] = t; }
+      if (durs[i] < durs[j]) {
+        i64 t   = durs[i];
+        durs[i] = durs[j];
+        durs[j] = t;
+      }
+
+  if (AVERAGE_FRAME_BIAS < 0. || AVERAGE_FRAME_BIAS  > 1.)
+    return durs[0];
 
   return durs[(i64) ((NUM_FRAMES_AVERAGED - 1) * AVERAGE_FRAME_BIAS)];
 }
@@ -914,6 +924,48 @@ static void drop_files_set_data_(i64 index, i64 data_size) {
   g_platform.drop_files[index].data      = _drop_files_buffer + offset;
 }
 
+i8 pixel_size_update_(i32 real_width, i32 real_height) {
+  i8 size_changed = 0;
+
+  i32 width  = real_width;
+  i32 height = real_height;
+
+  if (g_platform.pixel_size <= 0.)             g_platform.pixel_size = DEFAULT_PIXEL_SIZE;
+  if (g_platform.pixel_size <  MIN_PIXEL_SIZE) g_platform.pixel_size = MIN_PIXEL_SIZE;
+  if (g_platform.pixel_size >  MAX_PIXEL_SIZE) g_platform.pixel_size = MAX_PIXEL_SIZE;
+
+  if (g_platform.pixel_size > 1.) {
+    width  = (i32) floor(((f64) real_width)  / g_platform.pixel_size + .5);
+    height = (i32) floor(((f64) real_height) / g_platform.pixel_size + .5);
+  }
+
+  if (g_platform.real_width != real_width || g_platform.real_height != real_height) {
+    size_changed = 1;
+    g_platform.real_width  = real_width;
+    g_platform.real_height = real_height;
+  }
+
+  if (g_platform.frame_width != width || g_platform.frame_height != height) {
+    size_changed = 1;
+    g_platform.frame_width  = width;
+    g_platform.frame_height = height;
+  }
+
+  return size_changed;
+}
+
+void pixel_size_calubrate_(i64 current_frame_duration) {
+  if (g_platform.exact_resolution)
+    return;
+
+  i64 frame_duration = average_frame_duration_(current_frame_duration);
+
+  if (g_platform.pixel_size < MAX_PIXEL_SIZE && frame_duration > MAX_FRAME_DURATION)
+    g_platform.pixel_size += PIXEL_SIZE_DELTA * (frame_duration - MAX_FRAME_DURATION);
+  else if (g_platform.pixel_size > MIN_PIXEL_SIZE && frame_duration < MIN_FRAME_DURATION)
+    g_platform.pixel_size -= PIXEL_SIZE_DELTA * (MIN_FRAME_DURATION - frame_duration);
+}
+
 //  ================================================================
 //
 //  Unix
@@ -2108,29 +2160,7 @@ i32 p_handle_events(void) {
     _image.bytes_per_line = _image.width * 4;
   }
 
-  i32 width  = _image.width;
-  i32 height = _image.height;
-
-  if (g_platform.pixel_size <= 0.)             g_platform.pixel_size = DEFAULT_PIXEL_SIZE;
-  if (g_platform.pixel_size <  MIN_PIXEL_SIZE) g_platform.pixel_size = MIN_PIXEL_SIZE;
-  if (g_platform.pixel_size >  MAX_PIXEL_SIZE) g_platform.pixel_size = MAX_PIXEL_SIZE;
-
-  if (g_platform.pixel_size > 1.) {
-    width  = (i32) floor(((f64) _image.width)  / g_platform.pixel_size + .5);
-    height = (i32) floor(((f64) _image.height) / g_platform.pixel_size + .5);
-  }
-
-  if (g_platform.real_width != _image.width || g_platform.real_height != _image.height) {
-    ++num_events;
-    g_platform.real_width  = _image.width;
-    g_platform.real_height = _image.height;
-  }
-
-  if (g_platform.frame_width != width || g_platform.frame_height != height) {
-    ++num_events;
-    g_platform.frame_width  = width;
-    g_platform.frame_height = height;
-  }
+  num_events += pixel_size_update_(_image.width, _image.height);
 
   return num_events;
 }
@@ -2173,14 +2203,7 @@ void p_render_frame(void) {
   XPutImage(_display, _window, _gc, &_image, 0, 0, 0, 0, _image.width, _image.height);
   XFlush(_display);
 
-  if (!g_platform.exact_resolution) {
-    i64 frame_duration = average_frame_duration_(p_time() - _frame_time);
-
-    if (g_platform.pixel_size < MAX_PIXEL_SIZE && frame_duration > MAX_FRAME_DURATION)
-      g_platform.pixel_size += PIXEL_SIZE_DELTA * (frame_duration - MAX_FRAME_DURATION);
-    else if (g_platform.pixel_size > MIN_PIXEL_SIZE && frame_duration < MIN_FRAME_DURATION)
-      g_platform.pixel_size -= PIXEL_SIZE_DELTA * (MIN_FRAME_DURATION - frame_duration);
-  }
+  pixel_size_calubrate_(p_time() - _frame_time);
 }
 
 void p_clipboard_write(i64 size, c8 *data) {
@@ -2522,29 +2545,7 @@ __attribute__((export_name("js_frame"))) void js_frame(i32 frame_width, i32 fram
     _frame_height = frame_height;
   }
 
-  i32 width  = _frame_width;
-  i32 height = _frame_height;
-
-  if (g_platform.pixel_size <= 0.)             g_platform.pixel_size = DEFAULT_PIXEL_SIZE;
-  if (g_platform.pixel_size <  MIN_PIXEL_SIZE) g_platform.pixel_size = MIN_PIXEL_SIZE;
-  if (g_platform.pixel_size >  MAX_PIXEL_SIZE) g_platform.pixel_size = MAX_PIXEL_SIZE;
-
-  if (g_platform.pixel_size > 1.) {
-    width  = (i32) floor(((f64) _frame_width)  / g_platform.pixel_size + .5);
-    height = (i32) floor(((f64) _frame_height) / g_platform.pixel_size + .5);
-  }
-
-  if (g_platform.real_width != _frame_width || g_platform.real_height != _frame_height) {
-    ++_num_events;
-    g_platform.real_width  = _frame_width;
-    g_platform.real_height = _frame_height;
-  }
-
-  if (g_platform.frame_width != width || g_platform.frame_height != height) {
-    ++_num_events;
-    g_platform.frame_width  = width;
-    g_platform.frame_height = height;
-  }
+  _num_size += pixel_size_update_(_frame_width, _frame_height);
 
   g_platform.done = 0;
 
@@ -2565,14 +2566,8 @@ __attribute__((export_name("js_frame"))) void js_frame(i32 frame_width, i32 fram
 
   _sound_read = (_sound_read + num_samples * NUM_SOUND_CHANNELS) % MAX_NUM_SOUND_FRAMES;
 
-  if (!g_platform.exact_resolution && do_render) {
-    i64 frame_duration = average_frame_duration_(p_time() - frame_time);
-
-    if (g_platform.pixel_size < MAX_PIXEL_SIZE && frame_duration > MAX_FRAME_DURATION)
-      g_platform.pixel_size += PIXEL_SIZE_DELTA * (frame_duration - MAX_FRAME_DURATION);
-    else if (g_platform.pixel_size > MIN_PIXEL_SIZE && frame_duration < MIN_FRAME_DURATION)
-      g_platform.pixel_size -= PIXEL_SIZE_DELTA * (MIN_FRAME_DURATION - frame_duration);
-  }
+  if (do_render)
+    pixel_size_calubrate_(p_time() - frame_time);
 }
 
 __attribute__((export_name("js_mousemove"))) void js_mousemove(i32 x, i32 y) {