/*
* Dillo Widget
*
* 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.
*
* 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: 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: 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 width=%d height=%d bpp=%d gamma=%g\n",
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 ()
{
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