ImageBase.cpp

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/*
-----------------------------------------------------------------------------
This source file is part of VideoTexture library

Copyright (c) 2007 The Zdeno Ash Miklas

This program 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 2 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.
-----------------------------------------------------------------------------
*/

#include "ImageBase.h"
extern "C" {
#include "bgl.h"
}
#include "GL/glew.h"

#include <vector>
#include <string.h>

#include <PyObjectPlus.h>
#include <structmember.h>

#include "FilterBase.h"

#include "Exception.h"

#if (defined(WIN32) || defined(WIN64)) && !defined(FREE_WINDOWS)
#define strcasecmp  _stricmp
#endif

// ImageBase class implementation

// constructor
ImageBase::ImageBase (bool staticSrc) : m_image(NULL), m_imgSize(0),
m_avail(false), m_scale(false), m_scaleChange(false), m_flip(false),
m_staticSources(staticSrc), m_pyfilter(NULL)
{
    m_size[0] = m_size[1] = 0;
    m_exports = 0;
}


// destructor
ImageBase::~ImageBase (void)
{
    // release image
    if (m_image)
        delete [] m_image;
}


// release python objects
bool ImageBase::release (void)
{
    // iterate sources
    for (ImageSourceList::iterator it = m_sources.begin(); it != m_sources.end(); ++it)
    {
        // release source object
        delete *it;
        *it = NULL;
    }
    // release filter object
    Py_XDECREF(m_pyfilter);
    m_pyfilter = NULL;
    return true;
}


// get image
unsigned int * ImageBase::getImage (unsigned int texId, double ts)
{
    // if image is not available
    if (!m_avail)
    {
        // if there are any sources
        if (!m_sources.empty())
        {
            // get images from sources
            for (ImageSourceList::iterator it = m_sources.begin(); it != m_sources.end(); ++it)
                // get source image
                (*it)->getImage(ts);
            // init image
            init(m_sources[0]->getSize()[0], m_sources[0]->getSize()[1]);
        }
        // calculate new image
        calcImage(texId, ts);
    }
    // if image is available, return it, otherwise NULL
    return m_avail ? m_image : NULL;
}


// refresh image source
void ImageBase::refresh (void)
{
    // invalidate this image
    m_avail = false;
    // refresh all sources
    for (ImageSourceList::iterator it = m_sources.begin(); it != m_sources.end(); ++it)
        (*it)->refresh();
}


// get source object
PyImage * ImageBase::getSource (const char * id)
{
    // find source
    ImageSourceList::iterator src = findSource(id);
    // return it, if found
    return src != m_sources.end() ? (*src)->getSource() : NULL;
}


// set source object
bool ImageBase::setSource (const char * id, PyImage * source)
{
    // find source
    ImageSourceList::iterator src = findSource(id);
    // check source loop
    if (source != NULL && source->m_image->loopDetect(this))
        return false;
    // if found, set new object
    if (src != m_sources.end())
        // if new object is not empty or sources are static
        if (source != NULL || m_staticSources)
            // replace previous source
            (*src)->setSource(source);
        // otherwise delete source
        else
            m_sources.erase(src);
    // if source is not found and adding is allowed
    else
        if (!m_staticSources)
        {
            // create new source
            ImageSource * newSrc = newSource(id);
            newSrc->setSource(source);
            // if source was created, add it to source list
            if (newSrc != NULL) m_sources.push_back(newSrc);
        }
        // otherwise source wasn't set
        else 
            return false;
    // source was set
    return true;
}


// set pixel filter
void ImageBase::setFilter (PyFilter * filt)
{
    // reference new filter
    if (filt != NULL) Py_INCREF(filt);
    // release previous filter
    Py_XDECREF(m_pyfilter);
    // set new filter
    m_pyfilter = filt;
}

ExceptionID ImageHasExports;
ExceptionID InvalidColorChannel;

ExpDesc ImageHasExportsDesc (ImageHasExports, "Image has exported buffers, cannot resize");
ExpDesc InvalidColorChannelDesc (InvalidColorChannel, "Invalid or too many color channels specified. At most 4 values within R, G, B, A, 0, 1");

// initialize image data
void ImageBase::init (short width, short height)
{
    // if image has to be scaled
    if (m_scale)
    {
        // recalc sizes of image
        width = calcSize(width);
        height = calcSize(height);
    }
    // if sizes differ
    if (width != m_size[0] || height != m_size[1])
    {
        if (m_exports > 0)
            THRWEXCP(ImageHasExports,S_OK);

        // new buffer size
        unsigned int newSize = width * height;
        // if new buffer is larger than previous
        if (newSize > m_imgSize)
        {
            // set new buffer size
            m_imgSize = newSize;
            // release previous and create new buffer
            if (m_image)
                delete [] m_image;
            m_image = new unsigned int[m_imgSize];
        }
        // new image size
        m_size[0] = width;
        m_size[1] = height;
        // scale was processed
        m_scaleChange = false;
    }
}


// find source
ImageSourceList::iterator ImageBase::findSource (const char * id)
{
    // iterate sources
    ImageSourceList::iterator it;
    for (it = m_sources.begin(); it != m_sources.end(); ++it)
        // if id matches, return iterator
        if ((*it)->is(id)) return it;
    // source not found
    return it;
}


// check sources sizes
bool ImageBase::checkSourceSizes (void)
{
    // reference size
    short * refSize = NULL;
    // iterate sources
    for (ImageSourceList::iterator it = m_sources.begin(); it != m_sources.end(); ++it)
    {
        // get size of current source
        short * curSize = (*it)->getSize();
        // if size is available and is not empty
        if (curSize[0] != 0 && curSize[1] != 0) {
            // if reference size is not set
            if (refSize == NULL) {
                // set current size as reference
                refSize = curSize;
        // otherwise check with current size
            } else if (curSize[0] != refSize[0] || curSize[1] != refSize[1]) {
                // if they don't match, report it
                return false;
            }
        }
    }
    // all sizes match
    return true;
}


// compute nearest power of 2 value
short ImageBase::calcSize (short size)
{
    // while there is more than 1 bit in size value
    while ((size & (size - 1)) != 0)
        // clear last bit
        size = size & (size - 1);
    // return result
    return size;
}


// perform loop detection
bool ImageBase::loopDetect (ImageBase * img)
{
    // if this object is the same as parameter, loop is detected
    if (this == img) return true;
    // check all sources
    for (ImageSourceList::iterator it = m_sources.begin(); it != m_sources.end(); ++it)
        // if source detected loop, return this result
        if ((*it)->getSource() != NULL && (*it)->getSource()->m_image->loopDetect(img))
            return true;
    // no loop detected
    return false;
}


// ImageSource class implementation

// constructor
ImageSource::ImageSource (const char * id) : m_source(NULL), m_image(NULL)
{
    // copy id
    int idx;
    for (idx = 0; id[idx] != '\0' && idx < SourceIdSize - 1; ++idx)
        m_id[idx] = id[idx];
    m_id[idx] = '\0';
}

// destructor
ImageSource::~ImageSource (void)
{
    // release source
    setSource(NULL);
}


// compare id
bool ImageSource::is (const char * id)
{
    for (char * myId = m_id; *myId != '\0'; ++myId, ++id)
        if (*myId != *id) return false;
    return *id == '\0';
}


// set source object
void ImageSource::setSource (PyImage * source)
{
    // reference new source
    if (source != NULL) Py_INCREF(source);
    // release previous source
    Py_XDECREF(m_source);
    // set new source
    m_source = source;
}


// get image from source
unsigned int * ImageSource::getImage (double ts)
{
    // if source is available
    if (m_source != NULL)
        // get image from source
        m_image = m_source->m_image->getImage(0, ts);
    // otherwise reset buffer
    else
        m_image = NULL;
    // return image
    return m_image;
}


// refresh source
void ImageSource::refresh (void)
{
    // if source is available, refresh it
    if (m_source != NULL) m_source->m_image->refresh();
}



// list of image types
PyTypeList pyImageTypes;



// functions for python interface

// object allocation
PyObject * Image_allocNew (PyTypeObject * type, PyObject * args, PyObject * kwds)
{
    // allocate object
    PyImage * self = reinterpret_cast<PyImage*>(type->tp_alloc(type, 0));
    // initialize object structure
    self->m_image = NULL;
    // return allocated object
    return reinterpret_cast<PyObject*>(self);
}

// object deallocation
void Image_dealloc (PyImage * self)
{
    // release object attributes
    if (self->m_image != NULL)
    {
        if (self->m_image->m_exports > 0)
        {
            PyErr_SetString(PyExc_SystemError,
                            "deallocated Image object has exported buffers");
            PyErr_Print();
        }
        // if release requires deleting of object, do it
        if (self->m_image->release())
            delete self->m_image;
        self->m_image = NULL;
    }
}

// get image data
PyObject * Image_getImage (PyImage * self, char * mode)
{
    try
    {
        unsigned int * image = self->m_image->getImage();
        if (image) 
        {
            // build BGL buffer
            int dimensions = self->m_image->getBuffSize();
            Buffer * buffer;
            if (mode == NULL || !strcasecmp(mode, "RGBA"))
            {
                buffer = BGL_MakeBuffer( GL_BYTE, 1, &dimensions, image);
            }
            else 
            {
                int i, c, ncolor, pixels;
                int offset[4];
                unsigned char *s, *d;
                // scan the mode to get the channels requested, no more than 4
                for (i=ncolor=0; mode[i] != 0 && ncolor < 4; i++)
                {
                    switch (toupper(mode[i]))
                    {
                    case 'R':
                        offset[ncolor++] = 0;
                        break;
                    case 'G':
                        offset[ncolor++] = 1;
                        break;
                    case 'B':
                        offset[ncolor++] = 2;
                        break;
                    case 'A':
                        offset[ncolor++] = 3;
                        break;
                    case '0':
                        offset[ncolor++] = -1;
                        break;
                    case '1':
                        offset[ncolor++] = -2;
                        break;
                    // if you add more color code, change the switch further down
                    default:
                        THRWEXCP(InvalidColorChannel,S_OK);
                    }
                }
                if (mode[i] != 0) {
                    THRWEXCP(InvalidColorChannel,S_OK);
                }
                // first get the number of pixels
                pixels = dimensions / 4;
                // multiple by the number of channels, each is one byte
                dimensions = pixels * ncolor;
                // get an empty buffer
                buffer = BGL_MakeBuffer( GL_BYTE, 1, &dimensions, NULL);
                // and fill it
                for (i=0, d=(unsigned char*)buffer->buf.asbyte, s=(unsigned char*)image; 
                     i<pixels; 
                     ++i, d+=ncolor, s+=4)
                {
                    for (c=0; c<ncolor; c++)
                    {
                        switch (offset[c])
                        {
                        case 0: d[c] = s[0]; break;
                        case 1: d[c] = s[1]; break;
                        case 2: d[c] = s[2]; break;
                        case 3: d[c] = s[3]; break;
                        case -1: d[c] = 0; break;
                        case -2: d[c] = 0xFF; break;
                        }
                    }
                }
            }
            return (PyObject*)buffer;
        }
    }
    catch (Exception & exp)
    {
        exp.report();
        return NULL;
    }
    Py_RETURN_NONE;
}

// get image size
PyObject * Image_getSize (PyImage * self, void * closure)
{
    return Py_BuildValue("(hh)", self->m_image->getSize()[0],
        self->m_image->getSize()[1]);
}

// refresh image
PyObject * Image_refresh (PyImage * self)
{
    self->m_image->refresh();
    Py_RETURN_NONE;
}

// get scale
PyObject * Image_getScale (PyImage * self, void * closure)
{
    if (self->m_image != NULL && self->m_image->getScale()) Py_RETURN_TRUE;
    else Py_RETURN_FALSE;
}

// set scale
int Image_setScale (PyImage * self, PyObject * value, void * closure)
{
    // check parameter, report failure
    if (value == NULL || !PyBool_Check(value))
    {
        PyErr_SetString(PyExc_TypeError, "The value must be a bool");
        return -1;
    }
    // set scale
    if (self->m_image != NULL) self->m_image->setScale(value == Py_True);
    // success
    return 0;
}

// get flip
PyObject * Image_getFlip (PyImage * self, void * closure)
{
    if (self->m_image != NULL && self->m_image->getFlip()) Py_RETURN_TRUE;
    else Py_RETURN_FALSE;
}

// set flip
int Image_setFlip (PyImage * self, PyObject * value, void * closure)
{
    // check parameter, report failure
    if (value == NULL || !PyBool_Check(value))
    {
        PyErr_SetString(PyExc_TypeError, "The value must be a bool");
        return -1;
    }
    // set scale
    if (self->m_image != NULL) self->m_image->setFlip(value == Py_True);
    // success
    return 0;
}


// get filter source object
PyObject * Image_getSource (PyImage * self, PyObject * args)
{
    // get arguments
    char * id;
    if (!PyArg_ParseTuple(args, "s:getSource", &id))
        return NULL;
    if (self->m_image != NULL)
    {
        // get source object
        PyObject * src = reinterpret_cast<PyObject*>(self->m_image->getSource(id));
        // if source is available
        if (src != NULL)
        {
            // return source
            Py_INCREF(src);
            return src;
        }
    }
    // source was not found
    Py_RETURN_NONE;
}


// set filter source object
PyObject * Image_setSource (PyImage * self, PyObject * args)
{
    // get arguments
    char * id;
    PyObject * obj;
    if (!PyArg_ParseTuple(args, "sO:setSource", &id, &obj))
        return NULL;
    if (self->m_image != NULL)
    {
        // check type of object
        if (pyImageTypes.in(Py_TYPE(obj)))
        {
            // convert to image struct
            PyImage * img = reinterpret_cast<PyImage*>(obj);
            // set source
            if (!self->m_image->setSource(id, img))
            {
                // if not set, retport error
                PyErr_SetString(PyExc_RuntimeError, "Invalid source or id");
                return NULL;
            }
        }
        // else report error
        else
        {
            PyErr_SetString(PyExc_RuntimeError, "Invalid type of object");
            return NULL;
        }
    }
    // return none
    Py_RETURN_NONE;
}


// get pixel filter object
PyObject * Image_getFilter (PyImage * self, void * closure)
{
    // if image object is available
    if (self->m_image != NULL)
    {
        // pixel filter object
        PyObject * filt = reinterpret_cast<PyObject*>(self->m_image->getFilter());
        // if filter is present
        if (filt != NULL)
        {
            // return it
            Py_INCREF(filt);
            return filt;
        }
    }
    // otherwise return none
    Py_RETURN_NONE;
}


// set pixel filter object
int Image_setFilter (PyImage * self, PyObject * value, void * closure)
{
    // if image object is available
    if (self->m_image != NULL)
    {
        // check new value
        if (value == NULL || !pyFilterTypes.in(Py_TYPE(value)))
        {
            // report value error
            PyErr_SetString(PyExc_TypeError, "Invalid type of value");
            return -1;
        }
        // set new value
        self->m_image->setFilter(reinterpret_cast<PyFilter*>(value));
    }
    // return success
    return 0;
}
PyObject * Image_valid(PyImage * self, void * closure)
{
    if (self->m_image->isImageAvailable())
    {
        Py_RETURN_TRUE;
    }
    else
    {
        Py_RETURN_FALSE;
    }
}

int Image_getbuffer(PyImage *self, Py_buffer *view, int flags)
{
    unsigned int * image;
    int ret;

    try
    {
        // can throw in case of resize
        image = self->m_image->getImage();
    }
    catch (Exception & exp)
    {
        // cannot return -1, this creates a crash in Python, for now we will just return an empty buffer
        exp.report();
        //return -1;
        goto error;
    }

    if (!image)
    {
        // same remark, see above
        //PyErr_SetString(PyExc_BufferError, "Image buffer is not available");
        //return -1;
        goto error;
    }
    if (view == NULL)
    {
        self->m_image->m_exports++;
        return 0;
    }
    ret = PyBuffer_FillInfo(view, (PyObject*)self, image, self->m_image->getBuffSize(), 0, flags);
    if (ret >= 0)
        self->m_image->m_exports++;
    return ret;

error:
    // Return a empty buffer to avoid a crash in Python 3.1
    // The bug is fixed in Python SVN 77916, as soon as the python revision used by Blender is
    // updated, you can simply return -1 and set the error
    static char* buf = (char *)"";
    ret = PyBuffer_FillInfo(view, (PyObject*)self, buf, 0, 0, flags);
    if (ret >= 0)
        self->m_image->m_exports++;
    return ret;
    
}

void Image_releaseBuffer(PyImage *self, Py_buffer *buffer)
{
    self->m_image->m_exports--;
}

PyBufferProcs imageBufferProcs = 
{
    (getbufferproc)Image_getbuffer,
    (releasebufferproc)Image_releaseBuffer
};