blender/source/gameengine/VideoTexture/ImageMix.cpp
Benoit Bolsee 37b9c9fe4d VideoTexture: improvements to image data access API.
- Use BGL buffer instead of string for image data.
- Add buffer interface to image source.
- Allow customization of pixel format.
- Add valid property to check if the image data is available.

The image property of all Image source objects will now
return a BGL 'buffer' object. Previously it was returning
a string, which was not working at all with Python 3.1.
The BGL buffer type allows sequence access to bytes and
is directly usable in BGL OpenGL wrapper functions.
The buffer is formated as a 1 dimensional array of bytes
with 4 bytes per pixel in RGBA order.

BGL buffers will also be accepted in the ImageBuff load()
and plot() functions.

It is possible to customize the pixel format by using
the VideoTexture.imageToArray(image, mode) function:
the first argument is a Image source object, the second
optional argument is a format string using the R, G, B,
A, 0 and 1 characters. For example "BGR" means that each
pixel will be 3 bytes, corresponding to the Blue, Green
and Red channel in that order. Use 0 for a fixed hex 00
value, 1 for hex FF. The default mode is "RGBA".

All Image source objects now support the buffer interface
which allows to create memoryview objects for direct access
to the image internal buffer without memory copy. The buffer
format is one dimensional array of bytes with 4 bytes per
pixel in RGBA order. The buffer is writable, which allows
custom modifications of the image data.

v = memoryview(source)

A bug in the Python 3.1 buffer API will cause a crash if
the memoryview object cannot be created. Therefore, you
must always check first that an image data is available
before creating a memoryview object. Use the new valid
attribute for that:

if source.valid:
    v = memoryview(source)
    ...	

Note: the BGL buffer object itself does not yet support
the buffer interface.

Note: the valid attribute makes sense only if you use
image source in conjunction with texture object like this:

# refresh texture but keep image data in memory
texture.refresh(False)
if texture.source.valid:
    v = memoryview(texture.source)
    # process image
    ...
    # invalidate image for next texture refresh
    texture.source.refresh()

Limitation: While memoryview objects exist, the image cannot be
resized. Resizing occurs with ImageViewport objects when the
viewport size is changed or with ImageFFmpeg when a new image
is reloaded for example. Any attempt to resize will cause a
runtime error. Delete the memoryview objects is you want to
resize an image source object.
2010-02-21 22:20:00 +00:00

210 lines
6.6 KiB
C++

/* $Id$
-----------------------------------------------------------------------------
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.
-----------------------------------------------------------------------------
*/
// implementation
#include <PyObjectPlus.h>
#include <structmember.h>
#include "ImageMix.h"
#include "ImageBase.h"
#include "Exception.h"
// cast ImageSource pointer to ImageSourceMix
inline ImageSourceMix * getImageSourceMix (ImageSource * src)
{ return static_cast<ImageSourceMix*>(src); }
// get weight
short ImageMix::getWeight (const char * id)
{
// find source
ImageSourceList::iterator src = findSource(id);
// if found, return its weight
return src != m_sources.end() ? getImageSourceMix(*src)->getWeight() : 0;
}
// set weight
bool ImageMix::setWeight (const char * id, short weight)
{
// find source
ImageSourceList::iterator src = findSource(id);
// if source isn't found, report it
if (src == m_sources.end()) return false;
// set its weight
getImageSourceMix(*src)->setWeight(weight);
return true;
}
ExceptionID ImageSizesNotMatch;
ExpDesc ImageSizesNotMatchDesc (ImageSizesNotMatch, "Image sizes of sources are different");
// calculate image from sources and set its availability
void ImageMix::calcImage (unsigned int texId, double ts)
{
// check source sizes
if (!checkSourceSizes()) THRWEXCP(ImageSizesNotMatch, S_OK);
// set offsets to image buffers
for (ImageSourceList::iterator it = m_sources.begin(); it != m_sources.end(); ++it)
// if image buffer is available
if ((*it)->getImageBuf() != NULL)
// set its offset
getImageSourceMix(*it)->setOffset(m_sources[0]->getImageBuf());
// otherwise don't calculate image
else
return;
// if there is only single source
if (m_sources.size() == 1)
{
// use single filter
FilterBase mixFilt;
// fiter and convert image
filterImage(mixFilt, m_sources[0]->getImageBuf(), m_sources[0]->getSize());
}
// otherwise use mix filter to merge source images
else
{
FilterImageMix mixFilt (m_sources);
// fiter and convert image
filterImage(mixFilt, m_sources[0]->getImageBuf(), m_sources[0]->getSize());
}
}
// cast Image pointer to ImageMix
inline ImageMix * getImageMix (PyImage * self)
{ return static_cast<ImageMix*>(self->m_image); }
// python methods
// get source weight
PyObject * getWeight (PyImage * self, PyObject * args)
{
// weight
short weight = 0;
// get arguments
char * id;
if (!PyArg_ParseTuple(args, "s:getWeight", &id))
return NULL;
if (self->m_image != NULL)
// get weight
weight = getImageMix(self)->getWeight(id);
// return weight
return Py_BuildValue("h", weight);
}
// set source weight
PyObject * setWeight (PyImage * self, PyObject * args)
{
// get arguments
char * id;
short weight = 0;
if (!PyArg_ParseTuple(args, "sh:setWeight", &id, &weight))
return NULL;
if (self->m_image != NULL)
// set weight
if (!getImageMix(self)->setWeight(id, weight))
{
// if not set, report error
PyErr_SetString(PyExc_RuntimeError, "Invalid id of source");;
return NULL;
}
// return none
Py_RETURN_NONE;
}
// methods structure
static PyMethodDef imageMixMethods[] =
{
{"getSource", (PyCFunction)Image_getSource, METH_VARARGS, "get image source"},
{"setSource", (PyCFunction)Image_setSource, METH_VARARGS, "set image source"},
{"getWeight", (PyCFunction)getWeight, METH_VARARGS, "get image source weight"},
{"setWeight", (PyCFunction)setWeight, METH_VARARGS, "set image source weight"},
// methods from ImageBase class
{"refresh", (PyCFunction)Image_refresh, METH_NOARGS, "Refresh image - invalidate its current content"},
{NULL}
};
// attributes structure
static PyGetSetDef imageMixGetSets[] =
{ // attributes from ImageBase class
{(char*)"valid", (getter)Image_valid, NULL, (char*)"bool to tell if an image is available", NULL},
{(char*)"image", (getter)Image_getImage, NULL, (char*)"image data", NULL},
{(char*)"size", (getter)Image_getSize, NULL, (char*)"image size", NULL},
{(char*)"scale", (getter)Image_getScale, (setter)Image_setScale, (char*)"fast scale of image (near neighbour)", NULL},
{(char*)"flip", (getter)Image_getFlip, (setter)Image_setFlip, (char*)"flip image vertically", NULL},
{(char*)"filter", (getter)Image_getFilter, (setter)Image_setFilter, (char*)"pixel filter", NULL},
{NULL}
};
// define python type
PyTypeObject ImageMixType =
{
PyVarObject_HEAD_INIT(NULL, 0)
"VideoTexture.ImageMix", /*tp_name*/
sizeof(PyImage), /*tp_basicsize*/
0, /*tp_itemsize*/
(destructor)Image_dealloc, /*tp_dealloc*/
0, /*tp_print*/
0, /*tp_getattr*/
0, /*tp_setattr*/
0, /*tp_compare*/
0, /*tp_repr*/
0, /*tp_as_number*/
0, /*tp_as_sequence*/
0, /*tp_as_mapping*/
0, /*tp_hash */
0, /*tp_call*/
0, /*tp_str*/
0, /*tp_getattro*/
0, /*tp_setattro*/
&imageBufferProcs, /*tp_as_buffer*/
Py_TPFLAGS_DEFAULT, /*tp_flags*/
"Image mixer", /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
imageMixMethods, /* tp_methods */
0, /* tp_members */
imageMixGetSets, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */
0, /* tp_descr_set */
0, /* tp_dictoffset */
(initproc)Image_init<ImageMix>, /* tp_init */
0, /* tp_alloc */
Image_allocNew, /* tp_new */
};