/* This file is part of GEGL.
* ck
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see .
*
* Copyright 2008 Øyvind Kolås
*/
#ifndef __GEGL_BUFFER_ITERATOR_H__
#define __GEGL_BUFFER_ITERATOR_H__
#include "gegl-buffer.h"
#define GEGL_BUFFER_MAX_ITERATORS 6
#define GEGL_BUFFER_READ 1
#define GEGL_BUFFER_WRITE 2
#define GEGL_BUFFER_READWRITE (GEGL_BUFFER_READ|GEGL_BUFFER_WRITE)
typedef struct GeglBufferIterator
{
gint length;
gpointer data[GEGL_BUFFER_MAX_ITERATORS];
GeglRectangle roi[GEGL_BUFFER_MAX_ITERATORS];
gint level;
} GeglBufferIterator;
/**
* gegl_buffer_iterator_new:
* @buffer: a #GeglBuffer
* @roi: the rectangle to iterate over
* @format: the format we want to process this buffers data in, pass 0 to use the buffers format.
* @flags: whether we need reading or writing to this buffer one of GEGL_BUFFER_READ, GEGL_BUFFER_WRITE and GEGL_BUFFER_READWRITE.
* @level: the level at which we are iterating, the roi will indicate the
* extent at 1:1, x,y,width and height are/(2^level)
*
* Create a new buffer iterator, this buffer will be iterated through
* in linear chunks, some chunks might be full tiles the coordinates, see
* the documentation of gegl_buffer_iterator_next for how to use it and
* destroy it.
*
* Returns: a new buffer iterator that can be used to iterate through the
* buffers pixels.
*/
GeglBufferIterator * gegl_buffer_iterator_new (GeglBuffer *buffer,
const GeglRectangle *roi,
gint level,
const Babl *format,
guint flags,
GeglAbyssPolicy abyss_policy);
/**
* gegl_buffer_iterator_add:
* @iterator: a #GeglBufferIterator
* @buffer: a #GeglBuffer
* @roi: the rectangle to iterate over
* @format: the format we want to process this buffers data in, pass 0 to use the buffers format.
* @flags: whether we need reading or writing to this buffer.
*
* Adds an additional buffer iterator that will be processed in sync with
* the original one, if the buffer doesn't align with the other for tile access
* the corresponding scans and regions will be serialized automatically using
* gegl_buffer_get.
*
* Returns: an integer handle refering to the indice in the iterator structure
* of the added buffer.
*/
gint gegl_buffer_iterator_add (GeglBufferIterator *iterator,
GeglBuffer *buffer,
const GeglRectangle *roi,
gint level,
const Babl *format,
guint flags,
GeglAbyssPolicy abyss_policy);
/**
* gegl_buffer_iterator_stop:
* @iterator: a GeglBufferIterator
*
* Cancels the current iteration, freeing up any temporary resources. You have
* to bail out of any loop you are currently.
*/
void gegl_buffer_iterator_stop (GeglBufferIterator *iterator);
/**
* gegl_buffer_iterator_next:
* @iterator: a #GeglBufferIterator
*
* Do an iteration, this causes a new set of iterator->data[] to become
* available if there is more data to process. Changed data from a previous
* iteration step will also be saved now. When there is no more data to
* be processed FALSE will be returned (and the iterator handle is no longer
* valid).
*
* Returns: TRUE if there is more work FALSE if iteration is complete.
*/
gboolean gegl_buffer_iterator_next (GeglBufferIterator *iterator);
#ifdef EXAMPLE
GeglBufferIterator *gi;
gi = gegl_buffer_iterator_new (buffer, roi,
babl_format("Y' float"), GEGL_BUFFER_WRITE);
while (gegl_buffer_iterator_next (gi))
{
gfloat *buf = gi->data[0];
gint i;
for (i=0; ilength; i++)
{
buf[i]=0.5;
}
}
#endif
#endif