From d3071d1e50f261440d52aca22101b53051b29924 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Sat, 16 Apr 2016 14:19:54 +0200
Subject: [PATCH] Use a bitmask for storing clear-active flags

---
 panda/src/display/drawableRegion.I   | 18 +++++++++---------
 panda/src/display/drawableRegion.cxx | 23 ++++++++++-------------
 panda/src/display/drawableRegion.h   |  2 +-
 3 files changed, 20 insertions(+), 23 deletions(-)

diff --git a/panda/src/display/drawableRegion.I b/panda/src/display/drawableRegion.I
index b7bf511df6..677a345683 100644
--- a/panda/src/display/drawableRegion.I
+++ b/panda/src/display/drawableRegion.I
@@ -17,10 +17,10 @@
 INLINE DrawableRegion::
 DrawableRegion() :
   _screenshot_buffer_type(RenderBuffer::T_front),
-  _draw_buffer_type(RenderBuffer::T_back)
+  _draw_buffer_type(RenderBuffer::T_back),
+  _clear_mask(0)
 {
-  for (int i=0; i<RTP_COUNT; i++) {
-    _clear_active[i] = false;
+  for (int i = 0; i < RTP_COUNT; ++i) {
     _clear_value[i] = LColor(0.0f, 0.0f, 0.0f, 0.0f);
   }
   _clear_value[RTP_depth] = LColor(1.0f,1.0f,1.0f,1.0f);
@@ -35,11 +35,11 @@ INLINE DrawableRegion::
 DrawableRegion(const DrawableRegion &copy) :
   _screenshot_buffer_type(copy._screenshot_buffer_type),
   _draw_buffer_type(copy._draw_buffer_type),
+  _clear_mask(copy._clear_mask),
   _pixel_zoom(copy._pixel_zoom),
   _pixel_factor(copy._pixel_factor)
 {
-  for (int i=0; i<RTP_COUNT; i++) {
-    _clear_active[i] = copy._clear_active[i];
+  for (int i = 0; i < RTP_COUNT; ++i) {
     _clear_value[i] = copy._clear_value[i];
   }
 }
@@ -51,8 +51,8 @@ INLINE void DrawableRegion::
 operator = (const DrawableRegion &copy) {
   _screenshot_buffer_type = copy._screenshot_buffer_type;
   _draw_buffer_type = copy._draw_buffer_type;
-  for (int i=0; i<RTP_COUNT; i++) {
-    _clear_active[i] = copy._clear_active[i];
+  _clear_mask = copy._clear_mask;
+  for (int i = 0; i < RTP_COUNT; ++i) {
     _clear_value[i] = copy._clear_value[i];
   }
   _pixel_zoom = copy._pixel_zoom;
@@ -64,8 +64,8 @@ operator = (const DrawableRegion &copy) {
  */
 INLINE void DrawableRegion::
 copy_clear_settings(const DrawableRegion &copy) {
-  for (int i=0; i<RTP_COUNT; i++) {
-    _clear_active[i] = copy._clear_active[i];
+  _clear_mask = copy._clear_mask;
+  for (int i = 0; i < RTP_COUNT; ++i) {
     _clear_value[i] = copy._clear_value[i];
   }
   update_pixel_factor();
diff --git a/panda/src/display/drawableRegion.cxx b/panda/src/display/drawableRegion.cxx
index 3cebf7a808..eca8febc14 100644
--- a/panda/src/display/drawableRegion.cxx
+++ b/panda/src/display/drawableRegion.cxx
@@ -27,8 +27,12 @@ DrawableRegion::
  */
 void DrawableRegion::
 set_clear_active(int n, bool clear_active) {
-  nassertv((n >= 0)&&(n < RTP_COUNT));
-  _clear_active[n] = clear_active;
+  nassertv(n >= 0 && n < RTP_COUNT);
+  if (clear_active) {
+    _clear_mask |= 1 << n;
+  } else {
+    _clear_mask &= ~(1 << n);
+  }
   update_pixel_factor();
 }
 
@@ -37,8 +41,8 @@ set_clear_active(int n, bool clear_active) {
  */
 bool DrawableRegion::
 get_clear_active(int n) const {
-  nassertr((n >= 0)&&(n < RTP_COUNT), false);
-  return _clear_active[n];
+  nassertr(n >= 0 && n < RTP_COUNT, false);
+  return (_clear_mask & (1 << n)) != 0;
 }
 
 /**
@@ -66,9 +70,7 @@ get_clear_value(int n) const {
  */
 void DrawableRegion::
 disable_clears() {
-  for (int i = 0; i < RTP_COUNT; ++i) {
-    _clear_active[i] = false;
-  }
+  _clear_mask = 0;
   update_pixel_factor();
 }
 
@@ -79,12 +81,7 @@ disable_clears() {
  */
 bool DrawableRegion::
 is_any_clear_active() const {
-  for (int i = 0; i < RTP_COUNT; ++i) {
-    if (get_clear_active(i)) {
-      return true;
-    }
-  }
-  return false;
+  return (_clear_mask != 0);
 }
 
 /**
diff --git a/panda/src/display/drawableRegion.h b/panda/src/display/drawableRegion.h
index 10fafcf687..b5bb9bfd14 100644
--- a/panda/src/display/drawableRegion.h
+++ b/panda/src/display/drawableRegion.h
@@ -109,9 +109,9 @@ protected:
 protected:
   int _screenshot_buffer_type;
   int _draw_buffer_type;
+  int _clear_mask;
 
 private:
-  bool    _clear_active[RTP_COUNT];
   LColor  _clear_value[RTP_COUNT];
 
   PN_stdfloat _pixel_zoom;