Add tile buffering support

The TileBuffer class now manages all the tiles. The tile rendering calls
to LO core is also managed by this class.

Change-Id: Ic667a93dcf1c097e0601c0496e8a083c4742e8cb

1 files changed, 90 insertions, 0 deletions

diff --git a/libreofficekit/source/gtk/tilebuffer.cxx b/libreofficekit/source/gtk/tilebuffer.cxx
new file mode 100644
index 000000000000..ca66ae904f71
--- /dev/null
+++ b/libreofficekit/source/gtk/tilebuffer.cxx
@@ -0,0 +1,90 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include "tilebuffer.hxx"
+
+static const int DPI = 96;
+
+static float pixelToTwip(float fInput, float zoom)
+{
+    return (fInput / DPI / zoom) * 1440.0f;
+}
+
+static float twipToPixel(float fInput, float zoom)
+{
+    return fInput / 1440.0f * DPI * zoom;
+}
+
+GdkPixbuf* Tile::tile_get_buffer()
+{
+  return m_pBuffer;
+}
+
+void Tile::tile_release()
+{
+  gdk_pixbuf_unref(m_pBuffer);
+  m_pBuffer = NULL;
+}
+
+void TileBuffer::tile_buffer_set_zoom(float newZoomFactor, int rows, int columns)
+{
+  m_fZoomFactor = newZoomFactor;
+
+  tile_buffer_reset_all_tiles();
+
+  // set new buffer width and height
+  m_nWidth = columns;
+  m_nHeight = rows;
+  m_aTiles.resize(m_nWidth * m_nHeight);
+}
+
+void TileBuffer::tile_buffer_reset_all_tiles()
+{
+  for (size_t i = 0; i < m_aTiles.size(); i++)
+    {
+      m_aTiles[i].tile_release();
+    }
+  m_aTiles.clear();
+}
+
+Tile& TileBuffer::tile_buffer_get_tile(int x, int y)
+{
+  int index = x * m_nWidth + y;
+  if(!m_aTiles[index].valid)
+    {
+      GdkPixbuf* pPixBuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, TRUE, 8, m_nTileSize, m_nTileSize);
+      if (!pPixBuf){
+        g_info ("error allocating memory to pixbuf");
+      }
+      unsigned char* pBuffer = gdk_pixbuf_get_pixels(pPixBuf);
+      GdkRectangle aTileRectangle;
+      aTileRectangle.x = pixelToTwip(m_nTileSize, m_fZoomFactor) * y;
+      aTileRectangle.y = pixelToTwip(m_nTileSize, m_fZoomFactor) * x;
+
+      g_info ("rendering (%d %d)", x, y);
+      m_pLOKDocument->pClass->paintTile(m_pLOKDocument,
+                                        // Buffer and its size, depends on the position only.
+                                        pBuffer,
+                                        m_nTileSize, m_nTileSize,
+                                        // Position of the tile.
+                                        aTileRectangle.x, aTileRectangle.y,
+                                        // Size of the tile, depends on the zoom factor and the tile position only.
+                                        pixelToTwip(m_nTileSize, m_fZoomFactor), pixelToTwip(m_nTileSize, m_fZoomFactor));
+
+      m_aTiles[index].tile_set_pixbuf(pPixBuf);
+      m_aTiles[index].valid = 1;
+    }
+
+  return m_aTiles[index];
+}
+
+void Tile::tile_set_pixbuf(GdkPixbuf *buffer)
+{
+  m_pBuffer = buffer;
+}