From 9eaced3877cceb64a303fd79e2af23deb32bb5fc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Caol=C3=A1n=20McNamara?= <caolanm@redhat.com>
Date: Tue, 12 Feb 2013 14:51:58 +0000
Subject: [PATCH] doesn't help one bit

Change-Id: I6741cce6f752c3cd635d5594166f7cb13d53269a
---
 vcl/generic/glyphs/gcach_layout.cxx | 89 ++++++++++++++++++++++++++++++++++---
 1 file changed, 83 insertions(+), 6 deletions(-)

diff --git a/vcl/generic/glyphs/gcach_layout.cxx b/vcl/generic/glyphs/gcach_layout.cxx
index a9f373e..9e5d269 100644
--- a/vcl/generic/glyphs/gcach_layout.cxx
+++ b/vcl/generic/glyphs/gcach_layout.cxx
@@ -260,6 +260,59 @@ le_bool IcuFontFromServerFont::getGlyphPoint( LEGlyphID,
 
 // =======================================================================
 
+struct layoutCharsArgs
+{
+    const sal_Unicode *m_pChars;
+    le_int32 m_nOffset;
+    le_int32 m_nCount;
+    le_int32 m_nMax;
+    le_bool m_bRightToLeft;
+    float m_nX;
+    float m_nY;
+    layoutCharsArgs()
+        : m_pChars(NULL)
+        , m_nOffset(0)
+        , m_nCount(0)
+        , m_nMax(0)
+        , m_bRightToLeft(false)
+        , m_nX(0.0)
+        , m_nY(0.0)
+    {
+    }
+    layoutCharsArgs(const sal_Unicode *chars, le_int32 offset,
+        le_int32 count, le_int32 max, le_bool rightToLeft, float x, float y)
+        : m_pChars(chars)
+        , m_nOffset(offset)
+        , m_nCount(count)
+        , m_nMax(max)
+        , m_bRightToLeft(rightToLeft)
+        , m_nX(x)
+        , m_nY(y)
+    {
+    }
+    bool operator==(const layoutCharsArgs& rOther) const
+    {
+        return (m_pChars == rOther.m_pChars &&
+                m_nOffset == rOther.m_nOffset &&
+                m_nCount == rOther.m_nCount &&
+                m_nMax == rOther.m_nMax &&
+                m_bRightToLeft == rOther.m_bRightToLeft &&
+                m_nX == rOther.m_nX &&
+                m_nY == rOther.m_nY);
+    }
+};
+
+struct layoutCharsCache
+{
+    layoutCharsArgs m_aArgs;
+    le_int32        m_nRawRunGlyphCount;
+    LEErrorCode     m_nErrorCode;
+    void clear()
+    {
+        m_aArgs = layoutCharsArgs();
+    }
+};
+
 class IcuLayoutEngine : public ServerFontLayoutEngine
 {
 private:
@@ -269,6 +322,8 @@ private:
     le_int32                mnLayoutFlags;
     LayoutEngine*           mpIcuLE;
 
+    layoutCharsCache        maCache;
+
 public:
                             IcuLayoutEngine( ServerFont& );
     virtual                 ~IcuLayoutEngine();
@@ -385,6 +440,7 @@ bool IcuLayoutEngine::layout(ServerFontLayout& rLayout, ImplLayoutArgs& rArgs)
         {
             // TODO: cache multiple layout engines when multiple scripts are used
             delete mpIcuLE;
+            maCache.clear();
             meScriptCode = eScriptCode;
             mnLayoutFlags = nLayoutFlags;
             le_int32 eLangCode = 0; // TODO: get better value
@@ -400,11 +456,33 @@ bool IcuLayoutEngine::layout(ServerFontLayout& rLayout, ImplLayoutArgs& rArgs)
         if( !mpIcuLE )
             break;
 
-        // run ICU layout engine
-        // TODO: get enough context, remove extra glyps below
-        int nRawRunGlyphCount = mpIcuLE->layoutChars( pIcuChars,
-            nMinRunPos, nEndRunPos - nMinRunPos, rArgs.mnLength,
-            bRightToLeft, aNewPos.X(), aNewPos.Y(), rcIcu );
+        int nRawRunGlyphCount;
+
+        layoutCharsArgs aArgs(rArgs.mpStr, nMinRunPos, nEndRunPos - nMinRunPos, rArgs.mnLength,
+            bRightToLeft, aNewPos.X(), aNewPos.Y());
+
+        if (aArgs == maCache.m_aArgs)
+        {
+            nRawRunGlyphCount = maCache.m_nRawRunGlyphCount;
+            rcIcu = maCache.m_nErrorCode;
+        }
+        else
+        {
+            mpIcuLE->reset(); // frees the glyph, character index and position arrays
+                              // so that the LayoutEngine can be reused to layout a
+                              // different characer array
+
+            // run ICU layout engine
+            // TODO: get enough context, remove extra glyphs below
+            nRawRunGlyphCount = mpIcuLE->layoutChars(pIcuChars,
+                aArgs.m_nOffset, aArgs.m_nCount, aArgs.m_nMax,
+                aArgs.m_bRightToLeft, aArgs.m_nX, aArgs.m_nY, rcIcu );
+
+            maCache.m_aArgs = aArgs;
+            maCache.m_nRawRunGlyphCount = nRawRunGlyphCount;
+            maCache.m_nErrorCode = rcIcu;
+        }
+
         if( LE_FAILURE(rcIcu) )
             return false;
 
@@ -412,7 +490,6 @@ bool IcuLayoutEngine::layout(ServerFontLayout& rLayout, ImplLayoutArgs& rArgs)
         mpIcuLE->getGlyphs( pIcuGlyphs, rcIcu );
         mpIcuLE->getCharIndices( pCharIndices, rcIcu );
         mpIcuLE->getGlyphPositions( &pGlyphPositions->fX, rcIcu );
-        mpIcuLE->reset(); // TODO: get rid of this, PROBLEM: crash at exit when removed
         if( LE_FAILURE(rcIcu) )
             return false;
 
-- 
1.8.1.2