From 4b213f3039d9d2ea08ce4388ecb837e2f10cb1b1 Mon Sep 17 00:00:00 2001
From: David Capello <davidcapello@gmail.com>
Date: Thu, 25 Jun 2015 17:53:11 -0300
Subject: [PATCH] Improve selection tools performance

This commit reduce the number of computations needed to calculate the new
mask bounds. (E.g. avoiding get pixel calls in Mask::shrink().)
---
 src/app/tools/inks.h | 9 +++++++++
 src/doc/mask.cpp     | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/app/tools/inks.h b/src/app/tools/inks.h
index 126e717c4..af66d9f3c 100644
--- a/src/app/tools/inks.h
+++ b/src/app/tools/inks.h
@@ -254,6 +254,7 @@ public:
 class SelectionInk : public Ink {
   bool m_modify_selection;
   Mask m_mask;
+  Rect m_maxBounds;
 
 public:
   SelectionInk() { m_modify_selection = false; }
@@ -274,6 +275,8 @@ public:
           m_mask.subtract(gfx::Rect(x1-offset.x, y-offset.y, x2-x1+1, 1));
           break;
       }
+
+      m_maxBounds |= gfx::Rect(x1-offset.x, y-offset.y, x2-x1+1, 1);
     }
     // TODO show the selection-preview with a XOR color or something like that
     else {
@@ -287,11 +290,17 @@ public:
     m_modify_selection = state;
 
     if (state) {
+      m_maxBounds = gfx::Rect(0, 0, 0, 0);
+
       m_mask.copyFrom(loop->getMask());
       m_mask.freeze();
       m_mask.reserve(loop->sprite()->bounds());
     }
     else {
+      // We can intersect the used bounds in inkHline() calls to
+      // reduce the shrink computation.
+      m_mask.intersect(m_maxBounds);
+
       m_mask.unfreeze();
 
       loop->setMask(&m_mask);
diff --git a/src/doc/mask.cpp b/src/doc/mask.cpp
index fc1136d13..4225b4f08 100644
--- a/src/doc/mask.cpp
+++ b/src/doc/mask.cpp
@@ -385,7 +385,7 @@ void Mask::shrink()
   {                                                                     \
     for (u = u_begin; u u_op u_final; u u_add) {                        \
       for (v = v_begin; v v_op v_final; v v_add) {                      \
-        if (m_bitmap->getPixel(U, V))                                   \
+        if (get_pixel_fast<BitmapTraits>(m_bitmap.get(), U, V))         \
           break;                                                        \
       }                                                                 \
       if (v == v_final)                                                 \