Import RTFL 0.1.1v0.1.1

1 files changed, 584 insertions, 0 deletions

diff --git a/dw/fltkimgbuf.cc b/dw/fltkimgbuf.cc
new file mode 100644
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+++ b/dw/fltkimgbuf.cc
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+/*
+ * RTFL (originally part of dillo)
+ *
+ * Copyright 2005-2007, 2012-2013 Sebastian Geerken <sgeerken@dillo.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version; with the following exception:
+ *
+ * The copyright holders of RTFL give you permission to link this file
+ * statically or dynamically against all versions of the graphviz
+ * library, which are published by AT&T Corp. under one of the following
+ * licenses:
+ *
+ * - Common Public License version 1.0 as published by International
+ *   Business Machines Corporation (IBM), or
+ * - Eclipse Public License version 1.0 as published by the Eclipse
+ *   Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "fltkcore.hh"
+#include "../lout/msg.h"
+#include "../lout/misc.hh"
+
+#include <FL/fl_draw.H>
+#include <math.h>
+
+#define IMAGE_MAX_AREA (6000 * 6000)
+
+#define MAX_WIDTH 0x8000
+#define MAX_HEIGHT 0x8000
+
+namespace dw {
+namespace fltk {
+
+using namespace lout::container::typed;
+
+const enum ScaleMode { SIMPLE, BEAUTIFUL, BEAUTIFUL_GAMMA }
+   scaleMode = BEAUTIFUL_GAMMA;
+
+Vector <FltkImgbuf::GammaCorrectionTable> *FltkImgbuf::gammaCorrectionTables
+   = new Vector <FltkImgbuf::GammaCorrectionTable> (true, 2);
+
+uchar *FltkImgbuf::findGammaCorrectionTable (double gamma)
+{
+   // Since the number of possible keys is low, a linear search is
+   // sufficiently fast.
+
+   for (int i = 0; i < gammaCorrectionTables->size(); i++) {
+      GammaCorrectionTable *gct = gammaCorrectionTables->get(i);
+      if (gct->gamma == gamma)
+         return gct->map;
+   }
+
+   _MSG("Creating new table for gamma = %g\n", gamma);
+
+   GammaCorrectionTable *gct = new GammaCorrectionTable();
+   gct->gamma = gamma;
+
+   for (int i = 0; i < 256; i++)
+      gct->map[i] = 255 * pow((double)i / 255, gamma);
+
+   gammaCorrectionTables->put (gct);
+   return gct->map;
+}
+
+bool FltkImgbuf::excessiveImageDimensions (int width, int height)
+{
+   return width <= 0 || height <= 0 ||
+      width > IMAGE_MAX_AREA / height;
+}
+
+void FltkImgbuf::freeall ()
+{
+   _MSG("Deleting gammaCorrectionTables\n");
+   delete gammaCorrectionTables;
+   gammaCorrectionTables = NULL;
+}
+
+FltkImgbuf::FltkImgbuf (Type type, int width, int height, double gamma)
+{
+   DBG_OBJ_CREATE ("dw::fltk::FltkImgbuf");
+
+   _MSG ("FltkImgbuf::FltkImgbuf: new root %p\n", this);
+   init (type, width, height, gamma, NULL);
+}
+
+FltkImgbuf::FltkImgbuf (Type type, int width, int height, double gamma,
+                        FltkImgbuf *root)
+{
+   DBG_OBJ_CREATE ("dw::fltk::FltkImgbuf");
+
+   _MSG ("FltkImgbuf::FltkImgbuf: new scaled %p, root is %p\n", this, root);
+   init (type, width, height, gamma, root);
+}
+
+void FltkImgbuf::init (Type type, int width, int height, double gamma,
+                       FltkImgbuf *root)
+{
+   if (excessiveImageDimensions (width, height)) {
+      // Excessive image sizes which would cause crashes due to too
+      // big allocations for the image buffer (for root buffers, when
+      // the image was specially prepared). In this case we use a 1 x
+      // 1 size.
+      MSG("FltkImgbuf::init: suspicious image size request %d x %d\n",
+          width, height);
+      init (type, 1, 1, gamma, root);
+   } else if (width > MAX_WIDTH) {
+      // Too large dimensions cause dangerous overflow errors, so we
+      // limit dimensions to harmless values.
+      //
+      // Example: 65535 * 65536 / 65536 (see scaling below) results in
+      // the negative value -1.
+
+      MSG("FltkImgbuf::init: cannot handle large width %d\n", width);
+      init (type, MAX_WIDTH, height, gamma, root);
+   } else if (height > MAX_HEIGHT) {
+      MSG("FltkImgbuf::init: cannot handle large height %d\n", height);
+      init (type, width, MAX_HEIGHT, gamma, root);
+   } else if (gamma <= 0) {
+      MSG("FltkImgbuf::init: non-positive gamma %g\n", gamma);
+      init (type, width, height, 1, root);
+   } else {
+      this->root = root;
+      this->type = type;
+      this->width = width;
+      this->height = height;
+      this->gamma = gamma;
+
+      DBG_OBJ_SET_NUM ("width", width);
+      DBG_OBJ_SET_NUM ("height", height);
+
+      // TODO: Maybe this is only for root buffers
+      switch (type) {
+      case RGBA: bpp = 4; break;
+      case RGB:  bpp = 3; break;
+      default:   bpp = 1; break;
+      }
+      _MSG("FltkImgbuf::init this=%p width=%d height=%d bpp=%d gamma=%g\n",
+           this, width, height, bpp, gamma);
+      rawdata = new uchar[bpp * width * height];
+      // Set light-gray as interim background color.
+      memset(rawdata, 222, width*height*bpp);
+
+      refCount = 1;
+      deleteOnUnref = true;
+      copiedRows = new lout::misc::BitSet (height);
+
+      // The list is only used for root buffers.
+      if (isRoot())
+         scaledBuffers = new lout::container::typed::List <FltkImgbuf> (true);
+      else
+         scaledBuffers = NULL;
+
+      if (!isRoot()) {
+         // Scaling
+         for (int row = 0; row < root->height; row++) {
+            if (root->copiedRows->get (row))
+               scaleRow (row, root->rawdata + row*root->width*root->bpp);
+         }
+      }
+   }
+}
+
+FltkImgbuf::~FltkImgbuf ()
+{
+   _MSG ("FltkImgbuf::~FltkImgbuf\n");
+
+   if (!isRoot())
+      root->detachScaledBuf (this);
+
+   delete[] rawdata;
+   delete copiedRows;
+
+   if (scaledBuffers)
+      delete scaledBuffers;
+
+   DBG_OBJ_DELETE ();
+}
+
+/**
+ * \brief This method is called for the root buffer, when a scaled buffer
+ *    removed.
+ */
+void FltkImgbuf::detachScaledBuf (FltkImgbuf *scaledBuf)
+{
+   scaledBuffers->detachRef (scaledBuf);
+
+   _MSG("FltkImgbuf[root %p]: scaled buffer %p is detached, %d left\n",
+        this, scaledBuf, scaledBuffers->size ());
+
+   if (refCount == 0 && scaledBuffers->isEmpty () && deleteOnUnref)
+      // If the root buffer is not used anymore, but this is the last scaled
+      // buffer.
+      // See also: FltkImgbuf::unref().
+      delete this;
+}
+
+void FltkImgbuf::setCMap (int *colors, int num_colors)
+{
+}
+
+inline void FltkImgbuf::scaleRow (int row, const core::byte *data)
+{
+   if (row < root->height) {
+      if (scaleMode == SIMPLE)
+         scaleRowSimple (row, data);
+      else
+         scaleRowBeautiful (row, data);
+   }
+}
+
+inline void FltkImgbuf::scaleRowSimple (int row, const core::byte *data)
+{
+   int sr1 = scaledY (row);
+   int sr2 = scaledY (row + 1);
+
+   for (int sr = sr1; sr < sr2; sr++) {
+      // Avoid multiple passes.
+      if (copiedRows->get(sr)) continue;
+
+      copiedRows->set (sr, true);
+      if (sr == sr1) {
+         for (int px = 0; px < root->width; px++) {
+            int px1 = px * width / root->width;
+            int px2 = (px+1) * width / root->width;
+            for (int sp = px1; sp < px2; sp++) {
+               memcpy(rawdata + (sr*width + sp)*bpp, data + px*bpp, bpp);
+            }
+         }
+      } else {
+         memcpy(rawdata + sr*width*bpp, rawdata + sr1*width*bpp, width*bpp);
+      }
+   }
+}
+
+inline void FltkImgbuf::scaleRowBeautiful (int row, const core::byte *data)
+{
+   int sr1 = scaledY (row);
+   int sr2 = scaledY (row + 1);
+   bool allRootRows = false;
+
+   // Don't rescale rows!
+   if (copiedRows->get(sr1)) return;
+
+   if (height > root->height) {
+      scaleBuffer (data, root->width, 1,
+                   rawdata + sr1 * width * bpp, width, sr2 - sr1,
+                   bpp, gamma);
+      // Mark scaled rows done
+      for (int sr = sr1; sr < sr2 || sr == sr1; sr++)
+         copiedRows->set (sr, true);
+   } else {
+      assert (sr1 == sr2 || sr1 + 1 == sr2);
+      int row1 = backscaledY(sr1), row2 = backscaledY(sr1 + 1);
+
+      // Check all the necessary root lines already arrived,
+      // a larger area than a single row may be accessed here.
+      for (int r=row1; (allRootRows=root->copiedRows->get(r)) && ++r < row2; );
+      if (allRootRows) {
+         scaleBuffer (root->rawdata + row1 * root->width * bpp,
+                      root->width, row2 - row1,
+                      rawdata + sr1 * width * bpp, width, 1,
+                      bpp, gamma);
+         // Mark scaled row done
+         copiedRows->set (sr1, true);
+      }
+   }
+}
+
+/**
+ * General method to scale an image buffer. Used to scale single lines
+ * in scaleRowBeautiful.
+ *
+ * The algorithm is rather simple. If the scaled buffer is smaller
+ * (both width and height) than the original buffer, each pixel in the
+ * scaled buffer is assigned a rectangle of pixels in the original
+ * buffer; the resulting pixel value (red, green, blue) is simply the
+ * average of all pixel values. This is pretty fast and leads to
+ * rather good results.
+ *
+ * Nothing special (like interpolation) is done when scaling up.
+ *
+ * If scaleMode is set to BEAUTIFUL_GAMMA, gamma correction is
+ * considered, see <http://www.4p8.com/eric.brasseur/gamma.html>.
+ *
+ * TODO Could be optimized as in scaleRowSimple: when the destination
+ * image is larger, calculate only one row/column, and copy it to the
+ * other rows/columns.
+ */
+inline void FltkImgbuf::scaleBuffer (const core::byte *src, int srcWidth,
+                                     int srcHeight, core::byte *dest,
+                                     int destWidth, int destHeight, int bpp,
+                                     double gamma)
+{
+   uchar *gammaMap1, *gammaMap2;
+
+   if (scaleMode == BEAUTIFUL_GAMMA) {
+      gammaMap1 = findGammaCorrectionTable (gamma);
+      gammaMap2 = findGammaCorrectionTable (1 / gamma);
+   }
+
+   for(int x = 0; x < destWidth; x++)
+      for(int y = 0; y < destHeight; y++) {
+         int xo1 = x * srcWidth / destWidth;
+         int xo2 = lout::misc::max ((x + 1) * srcWidth / destWidth, xo1 + 1);
+         int yo1 = y * srcHeight / destHeight;
+         int yo2 = lout::misc::max ((y + 1) * srcHeight / destHeight, yo1 + 1);
+         int n = (xo2 - xo1) * (yo2 - yo1);
+
+         int v[bpp];
+         for(int i = 0; i < bpp; i++)
+            v[i] = 0;
+
+         for(int xo = xo1; xo < xo2; xo++)
+            for(int yo = yo1; yo < yo2; yo++) {
+               const core::byte *ps = src + bpp * (yo * srcWidth + xo);
+               for(int i = 0; i < bpp; i++)
+                  v[i] +=
+                     (scaleMode == BEAUTIFUL_GAMMA ? gammaMap2[ps[i]] : ps[i]);
+            }
+
+         core::byte *pd = dest + bpp * (y * destWidth + x);
+         for(int i = 0; i < bpp; i++)
+            pd[i] =
+               scaleMode == BEAUTIFUL_GAMMA ? gammaMap1[v[i] / n] : v[i] / n;
+      }
+}
+
+void FltkImgbuf::copyRow (int row, const core::byte *data)
+{
+   assert (isRoot());
+
+   if (row < height) {
+      // Flag the row done and copy its data.
+      copiedRows->set (row, true);
+      memcpy(rawdata + row * width * bpp, data, width * bpp);
+
+      // Update all the scaled buffers of this root image.
+      for (Iterator <FltkImgbuf> it = scaledBuffers->iterator();
+           it.hasNext(); ) {
+         FltkImgbuf *sb = it.getNext ();
+         sb->scaleRow (row, data);
+      }
+   }
+}
+
+void FltkImgbuf::newScan ()
+{
+   if (isRoot()) {
+      for (Iterator<FltkImgbuf> it = scaledBuffers->iterator(); it.hasNext();){
+         FltkImgbuf *sb = it.getNext ();
+         sb->copiedRows->clear();
+      }
+   }
+}
+
+core::Imgbuf* FltkImgbuf::getScaledBuf (int width, int height)
+{
+   if (!isRoot())
+      return root->getScaledBuf (width, height);
+
+   if (width > MAX_WIDTH) {
+      // Similar to init.
+      MSG("FltkImgbuf::getScaledBuf: cannot handle large width %d\n", width);
+      return getScaledBuf (MAX_WIDTH, height);
+   }
+   if (height > MAX_HEIGHT) {
+      MSG("FltkImgbuf::getScaledBuf: cannot handle large height %d\n", height);
+      return getScaledBuf (width, MAX_HEIGHT);
+   }
+
+   if (width == this->width && height == this->height) {
+      ref ();
+      return this;
+   }
+
+   for (Iterator <FltkImgbuf> it = scaledBuffers->iterator(); it.hasNext(); ) {
+      FltkImgbuf *sb = it.getNext ();
+      if (sb->width == width && sb->height == height) {
+         sb->ref ();
+         return sb;
+      }
+   }
+
+   // Check for excessive image sizes which would cause crashes due to
+   // too big allocations for the image buffer. In this case we return
+   // a pointer to the unscaled image buffer.
+   if (excessiveImageDimensions (width, height)) {
+      MSG("FltkImgbuf::getScaledBuf: suspicious image size request %d x %d\n",
+           width, height);
+      ref ();
+      return this;
+   }
+
+   // This size is not yet used, so a new buffer has to be created.
+   FltkImgbuf *sb = new FltkImgbuf (type, width, height, gamma, this);
+   scaledBuffers->append (sb);
+   DBG_OBJ_ASSOC_CHILD (sb);
+
+   return sb;
+}
+
+void FltkImgbuf::getRowArea (int row, dw::core::Rectangle *area)
+{
+   // TODO: May have to be adjusted.
+
+   if (isRoot()) {
+      /* root buffer */
+      area->x = 0;
+      area->y = row;
+      area->width = width;
+      area->height = 1;
+      _MSG("::getRowArea: area x=%d y=%d width=%d height=%d\n",
+           area->x, area->y, area->width, area->height);
+   } else {
+      if (row > root->height)
+         area->x = area->y = area->width = area->height = 0;
+      else {
+         // scaled buffer
+         int sr1 = scaledY (row);
+         int sr2 = scaledY (row + 1);
+
+         area->x = 0;
+         area->y = sr1;
+         area->width = width;
+         area->height = sr2 - sr1;
+         _MSG("::getRowArea: area x=%d y=%d width=%d height=%d\n",
+              area->x, area->y, area->width, area->height);
+      }
+   }
+}
+
+int FltkImgbuf::getRootWidth ()
+{
+   return root ? root->width : width;
+}
+
+int FltkImgbuf::getRootHeight ()
+{
+   return root ? root->height : height;
+}
+
+core::Imgbuf *FltkImgbuf::createSimilarBuf (int width, int height)
+{
+   return new FltkImgbuf (type, width, height, gamma);
+}
+
+void FltkImgbuf::copyTo (Imgbuf *dest, int xDestRoot, int yDestRoot,
+                         int xSrc, int ySrc, int widthSrc, int heightSrc)
+{
+   FltkImgbuf *fDest = (FltkImgbuf*)dest;
+   assert (bpp == fDest->bpp);
+
+   int xSrc2 = lout::misc::min (xSrc + widthSrc, fDest->width - xDestRoot);
+   int ySrc2 = lout::misc::min (ySrc + heightSrc, fDest->height - yDestRoot);
+
+   //printf ("copying from (%d, %d), %d x %d to (%d, %d) (root) => "
+   //        "xSrc2 = %d, ySrc2 = %d\n",
+   //        xSrc, ySrc, widthSrc, heightSrc, xDestRoot, yDestRoot,
+   //        xSrc2, ySrc2);
+
+   for (int x = xSrc; x < xSrc2; x++)
+      for (int y = ySrc; y < ySrc2; y++) {
+         int iSrc = x + width * y;
+         int iDest = xDestRoot + x + fDest->width * (yDestRoot + y);
+
+         //printf ("   (%d, %d): %d -> %d\n", x, y, iSrc, iDest);
+
+         for (int b = 0; b < bpp; b++)
+            fDest->rawdata[bpp * iDest + b] = rawdata[bpp * iSrc + b];
+      }
+}
+
+void FltkImgbuf::ref ()
+{
+   refCount++;
+
+   //if (root)
+   //   MSG("FltkImgbuf[scaled %p, root is %p]: ref() => %d\n",
+   //        this, root, refCount);
+   //else
+   //   MSG("FltkImgbuf[root %p]: ref() => %d\n", this, refCount);
+}
+
+void FltkImgbuf::unref ()
+{
+   //if (root)
+   //   MSG("FltkImgbuf[scaled %p, root is %p]: ref() => %d\n",
+   //       this, root, refCount - 1);
+   //else
+   //   MSG("FltkImgbuf[root %p]: ref() => %d\n", this, refCount - 1);
+
+   if (--refCount == 0) {
+      if (isRoot ()) {
+         // Root buffer, it must be ensured that no scaled buffers are left.
+         // See also FltkImgbuf::detachScaledBuf().
+         if (scaledBuffers->isEmpty () && deleteOnUnref) {
+            delete this;
+         } else {
+            _MSG("FltkImgbuf[root %p]: not deleted. numScaled=%d\n",
+                 this, scaledBuffers->size ());
+         }
+      } else
+         // Scaled buffer buffer, simply delete it.
+         delete this;
+   }
+}
+
+bool FltkImgbuf::lastReference ()
+{
+   return refCount == 1 &&
+      (scaledBuffers == NULL || scaledBuffers->isEmpty ());
+}
+
+void FltkImgbuf::setDeleteOnUnref (bool deleteOnUnref)
+{
+   assert (isRoot ());
+   this->deleteOnUnref = deleteOnUnref;
+}
+
+bool FltkImgbuf::isReferred ()
+{
+   return refCount != 0 ||
+      (scaledBuffers != NULL && !scaledBuffers->isEmpty ());
+}
+
+
+int FltkImgbuf::scaledY(int ySrc)
+{
+   // TODO: May have to be adjusted.
+   assert (root != NULL);
+   return ySrc * height / root->height;
+}
+
+int FltkImgbuf::backscaledY(int yScaled)
+{
+   assert (root != NULL);
+
+   // Notice that rounding errors because of integers do not play a
+   // role. This method cannot be the exact inverse of scaledY, since
+   // scaleY is not bijective, and so not invertible. Instead, both
+   // values always return the smallest value.
+   return yScaled * root->height / height;
+}
+
+void FltkImgbuf::draw (Fl_Widget *target, int xRoot, int yRoot,
+                       int x, int y, int width, int height)
+{
+   // TODO: Clarify the question, whether "target" is the current widget
+   //       (and so has not to be passed at all).
+
+   _MSG("::draw: xRoot=%d x=%d yRoot=%d y=%d width=%d height=%d\n"
+        "        this->width=%d this->height=%d\n",
+        xRoot, x, yRoot, y, width, height, this->width, this->height);
+
+   if (x > this->width || y > this->height) {
+      return;
+   }
+
+   if (x + width > this->width) {
+      width = this->width - x;
+   }
+
+   if (y + height > this->height) {
+      height = this->height - y;
+   }
+
+   fl_draw_image(rawdata+bpp*(y*this->width + x), xRoot + x, yRoot + y, width,
+                 height, bpp, this->width * bpp);
+
+}
+
+} // namespace fltk
+} // namespace dw