Hi Thomas,
On Fri, Dec 3, 2010 at 7:05 AM, Thomas Hogarth <[email protected]> wrote:
> Hi Robert
> Attached is a simple example demonstrating my NPOT subload issue.
I have tested your example and reproduced the constant rebuild of the
texture object, and using this have dug into the Texture2D::apply()
method to under stand what is going on.
What is clear from the existing code is that the problem will exist
when you assign an osg::Image to a texture and use a subload callback
to create a texture object of a different size to that Image. There
is specific code in Texture2D::apply() to catch when Images changes
size or format, but this code ignores the presence of the callback.
A quick fix is to only do the check for changes in image size and
pixel format when no callback is attached. The attached Texture2D.cpp
does just this and is attached. The change is pretty simple:
Index: Texture2D.cpp
===================================================================
--- Texture2D.cpp (revision 11975)
+++ Texture2D.cpp (working copy)
@@ -144,7 +144,7 @@
if (textureObject)
{
- if (_image.valid() && getModifiedCount(contextID) !=
_image->getModifiedCount())
+ if (!_subloadCallback && _image.valid() &&
getModifiedCount(contextID) != _image->getModifiedCount())
{
// compute the internal texture format, this set the
_internalFormat to an appropriate value.
computeInternalFormat();
While this is pretty easy change, it does push the responsibility of
catching when the texture object needs to be re-assigned due to
changes in the pixel format or size to the callback. This is no great
problem, but it's a rather implicit change in behaviour. In your
usage case it'll fix a problem, but just as easily it could break
other applications that rely upon the existing behaviour.
I'm currently learning towards doing what we did with the
Callback::generateTextureObject() method, and letting the callback
decide whether the re-assignment of the texture object is required,
and by default have this method provide the existing behaviour of
doing the resize if the image changes size or pixel format.
I'm not sure of what form this method needs to take yet.. will do some
further thinking on the topic.
Robert.
/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* 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
* OpenSceneGraph Public License for more details.
*/
#include <osg/GLExtensions>
#include <osg/Texture2D>
#include <osg/State>
#include <osg/Notify>
using namespace osg;
Texture2D::Texture2D():
_textureWidth(0),
_textureHeight(0),
_numMipmapLevels(0)
{
setUseHardwareMipMapGeneration(true);
}
Texture2D::Texture2D(Image* image):
_textureWidth(0),
_textureHeight(0),
_numMipmapLevels(0)
{
setUseHardwareMipMapGeneration(true);
setImage(image);
}
Texture2D::Texture2D(const Texture2D& text,const CopyOp& copyop):
Texture(text,copyop),
_image(copyop(text._image.get())),
_textureWidth(text._textureWidth),
_textureHeight(text._textureHeight),
_numMipmapLevels(text._numMipmapLevels),
_subloadCallback(text._subloadCallback)
{
}
Texture2D::~Texture2D()
{
}
int Texture2D::compare(const StateAttribute& sa) const
{
// check the types are equal and then create the rhs variable
// used by the COMPARE_StateAttribute_Parameter macros below.
COMPARE_StateAttribute_Types(Texture2D,sa)
if (_image!=rhs._image) // smart pointer comparison.
{
if (_image.valid())
{
if (rhs._image.valid())
{
int result = _image->compare(*rhs._image);
if (result!=0) return result;
}
else
{
return 1; // valid lhs._image is greater than null.
}
}
else if (rhs._image.valid())
{
return -1; // valid rhs._image is greater than null.
}
}
if (!_image && !rhs._image)
{
// no image attached to either Texture2D
// but could these textures already be downloaded?
// check the _textureObjectBuffer to see if they have been
// downloaded
int result = compareTextureObjects(rhs);
if (result!=0) return result;
}
int result = compareTexture(rhs);
if (result!=0) return result;
// compare each parameter in turn against the rhs.
#if 1
if (_textureWidth != 0 && rhs._textureWidth != 0)
{
COMPARE_StateAttribute_Parameter(_textureWidth)
}
if (_textureHeight != 0 && rhs._textureHeight != 0)
{
COMPARE_StateAttribute_Parameter(_textureHeight)
}
#endif
COMPARE_StateAttribute_Parameter(_subloadCallback)
return 0; // passed all the above comparison macros, must be equal.
}
void Texture2D::setImage(Image* image)
{
if (_image == image) return;
if (_image.valid() && _image->requiresUpdateCall())
{
setUpdateCallback(0);
setDataVariance(osg::Object::STATIC);
}
_image = image;
_modifiedCount.setAllElementsTo(0);
if (_image.valid() && _image->requiresUpdateCall())
{
setUpdateCallback(new Image::UpdateCallback());
setDataVariance(osg::Object::DYNAMIC);
}
}
void Texture2D::apply(State& state) const
{
//state.setReportGLErrors(true);
// get the contextID (user defined ID of 0 upwards) for the
// current OpenGL context.
const unsigned int contextID = state.getContextID();
Texture::TextureObjectManager* tom = Texture::getTextureObjectManager(contextID).get();
ElapsedTime elapsedTime(&(tom->getApplyTime()));
tom->getNumberApplied()++;
// get the texture object for the current contextID.
TextureObject* textureObject = getTextureObject(contextID);
if (textureObject)
{
if (!_subloadCallback && _image.valid() && getModifiedCount(contextID) != _image->getModifiedCount())
{
// compute the internal texture format, this set the _internalFormat to an appropriate value.
computeInternalFormat();
GLsizei new_width, new_height, new_numMipmapLevels;
// compute the dimensions of the texture.
computeRequiredTextureDimensions(state, *_image, new_width, new_height, new_numMipmapLevels);
if (!textureObject->match(GL_TEXTURE_2D, new_numMipmapLevels, _internalFormat, new_width, new_height, 1, _borderWidth))
{
Texture::releaseTextureObject(contextID, _textureObjectBuffer[contextID].get());
_textureObjectBuffer[contextID] = 0;
textureObject = 0;
}
}
}
if (textureObject)
{
textureObject->bind();
if (getTextureParameterDirty(state.getContextID()))
applyTexParameters(GL_TEXTURE_2D,state);
if (_subloadCallback.valid())
{
_subloadCallback->subload(*this,state);
}
else if (_image.valid() && getModifiedCount(contextID) != _image->getModifiedCount())
{
applyTexImage2D_subload(state,GL_TEXTURE_2D,_image.get(),
_textureWidth, _textureHeight, _internalFormat, _numMipmapLevels);
// update the modified tag to show that it is up to date.
getModifiedCount(contextID) = _image->getModifiedCount();
}
else if (_readPBuffer.valid())
{
_readPBuffer->bindPBufferToTexture(GL_FRONT);
}
}
else if (_subloadCallback.valid())
{
_textureObjectBuffer[contextID] = textureObject = _subloadCallback->generateTextureObject(*this, state);
textureObject->bind();
applyTexParameters(GL_TEXTURE_2D,state);
_subloadCallback->load(*this,state);
textureObject->setAllocated(_numMipmapLevels,_internalFormat,_textureWidth,_textureHeight,1,_borderWidth);
// in theory the following line is redundent, but in practice
// have found that the first frame drawn doesn't apply the textures
// unless a second bind is called?!!
// perhaps it is the first glBind which is not required...
//glBindTexture( GL_TEXTURE_2D, handle );
// update the modified tag to show that it is upto date.
if (_image.valid()) getModifiedCount(contextID) = _image->getModifiedCount();
}
else if (_image.valid() && _image->data())
{
// keep the image around at least till we go out of scope.
osg::ref_ptr<osg::Image> image = _image;
// compute the internal texture format, this set the _internalFormat to an appropriate value.
computeInternalFormat();
// compute the dimensions of the texture.
computeRequiredTextureDimensions(state,*image,_textureWidth, _textureHeight, _numMipmapLevels);
_textureObjectBuffer[contextID] = textureObject = generateTextureObject(
this, contextID,GL_TEXTURE_2D,_numMipmapLevels,_internalFormat,_textureWidth,_textureHeight,1,_borderWidth);
textureObject->bind();
applyTexParameters(GL_TEXTURE_2D,state);
if (textureObject->isAllocated())
{
//OSG_NOTICE<<"Reusing texture object"<<std::endl;
applyTexImage2D_subload(state,GL_TEXTURE_2D,image.get(),
_textureWidth, _textureHeight, _internalFormat, _numMipmapLevels);
}
else
{
//OSG_NOTICE<<"Creating new texture object"<<std::endl;
applyTexImage2D_load(state,GL_TEXTURE_2D,image.get(),
_textureWidth, _textureHeight, _numMipmapLevels);
textureObject->setAllocated(true);
}
// update the modified tag to show that it is upto date.
getModifiedCount(contextID) = image->getModifiedCount();
// unref image data?
if (isSafeToUnrefImageData(state) && image->getDataVariance()==STATIC)
{
Texture2D* non_const_this = const_cast<Texture2D*>(this);
non_const_this->_image = NULL;
}
// in theory the following line is redundent, but in practice
// have found that the first frame drawn doesn't apply the textures
// unless a second bind is called?!!
// perhaps it is the first glBind which is not required...
//glBindTexture( GL_TEXTURE_2D, handle );
}
else if ( (_textureWidth!=0) && (_textureHeight!=0) && (_internalFormat!=0) )
{
_textureObjectBuffer[contextID] = textureObject = generateTextureObject(
this, contextID,GL_TEXTURE_2D,_numMipmapLevels,_internalFormat,_textureWidth,_textureHeight,1,_borderWidth);
textureObject->bind();
applyTexParameters(GL_TEXTURE_2D,state);
// no image present, but dimensions at set so lets create the texture
glTexImage2D( GL_TEXTURE_2D, 0, _internalFormat,
_textureWidth, _textureHeight, _borderWidth,
_sourceFormat ? _sourceFormat : _internalFormat,
_sourceType ? _sourceType : GL_UNSIGNED_BYTE,
0);
if (_readPBuffer.valid())
{
_readPBuffer->bindPBufferToTexture(GL_FRONT);
}
}
else
{
glBindTexture( GL_TEXTURE_2D, 0 );
}
// if texture object is now valid and we have to allocate mipmap levels, then
if (textureObject != 0 && _texMipmapGenerationDirtyList[contextID])
{
generateMipmap(state);
}
}
void Texture2D::computeInternalFormat() const
{
if (_image.valid()) computeInternalFormatWithImage(*_image);
else computeInternalFormatType();
}
void Texture2D::copyTexImage2D(State& state, int x, int y, int width, int height )
{
const unsigned int contextID = state.getContextID();
if (_internalFormat==0) _internalFormat=GL_RGBA;
// get the globj for the current contextID.
TextureObject* textureObject = getTextureObject(contextID);
if (textureObject)
{
if (width==(int)_textureWidth && height==(int)_textureHeight)
{
// we have a valid texture object which is the right size
// so lets play clever and use copyTexSubImage2D instead.
// this allows use to reuse the texture object and avoid
// expensive memory allocations.
copyTexSubImage2D(state,0 ,0, x, y, width, height);
return;
}
// the relevent texture object is not of the right size so
// needs to been deleted
// remove previously bound textures.
dirtyTextureObject();
// note, dirtyTextureObject() dirties all the texture objects for
// this texture, is this right? Perhaps we should dirty just the
// one for this context. Note sure yet will leave till later.
// RO July 2001.
}
// remove any previously assigned images as these are nolonger valid.
_image = NULL;
// switch off mip-mapping.
//
bool needHardwareMipMap = (_min_filter != LINEAR && _min_filter != NEAREST);
bool hardwareMipMapOn = false;
if (needHardwareMipMap)
{
hardwareMipMapOn = isHardwareMipmapGenerationEnabled(state);
if (!hardwareMipMapOn)
{
// have to switch off mip mapping
OSG_NOTICE<<"Warning: Texture2D::copyTexImage2D(,,,,) switch off mip mapping as hardware support not available."<<std::endl;
_min_filter = LINEAR;
}
}
_textureWidth = width;
_textureHeight = height;
_numMipmapLevels = 1;
if (needHardwareMipMap)
{
for(int s=1; s<width || s<height; s <<= 1, ++_numMipmapLevels) {}
}
_textureObjectBuffer[contextID] = textureObject = generateTextureObject(this, contextID,GL_TEXTURE_2D,_numMipmapLevels,_internalFormat,_textureWidth,_textureHeight,1,0);
textureObject->bind();
applyTexParameters(GL_TEXTURE_2D,state);
GenerateMipmapMode mipmapResult = mipmapBeforeTexImage(state, hardwareMipMapOn);
glCopyTexImage2D( GL_TEXTURE_2D, 0, _internalFormat, x, y, width, height, 0 );
mipmapAfterTexImage(state, mipmapResult);
textureObject->setAllocated(true);
// inform state that this texture is the current one bound.
state.haveAppliedTextureAttribute(state.getActiveTextureUnit(), this);
}
void Texture2D::copyTexSubImage2D(State& state, int xoffset, int yoffset, int x, int y, int width, int height )
{
const unsigned int contextID = state.getContextID();
if (_internalFormat==0) _internalFormat=GL_RGBA;
// get the texture object for the current contextID.
TextureObject* textureObject = getTextureObject(contextID);
if (textureObject)
{
// we have a valid image
textureObject->bind();
applyTexParameters(GL_TEXTURE_2D,state);
bool needHardwareMipMap = (_min_filter != LINEAR && _min_filter != NEAREST);
bool hardwareMipMapOn = false;
if (needHardwareMipMap)
{
hardwareMipMapOn = isHardwareMipmapGenerationEnabled(state);
if (!hardwareMipMapOn)
{
// have to switch off mip mapping
OSG_NOTICE<<"Warning: Texture2D::copyTexImage2D(,,,,) switch off mip mapping as hardware support not available."<<std::endl;
_min_filter = LINEAR;
}
}
GenerateMipmapMode mipmapResult = mipmapBeforeTexImage(state, hardwareMipMapOn);
glCopyTexSubImage2D( GL_TEXTURE_2D, 0, xoffset, yoffset, x, y, width, height);
mipmapAfterTexImage(state, mipmapResult);
// inform state that this texture is the current one bound.
state.haveAppliedTextureAttribute(state.getActiveTextureUnit(), this);
}
else
{
// no texture object already exsits for this context so need to
// create it upfront - simply call copyTexImage2D.
copyTexImage2D(state,x,y,width,height);
}
}
void Texture2D::allocateMipmap(State& state) const
{
const unsigned int contextID = state.getContextID();
// get the texture object for the current contextID.
TextureObject* textureObject = getTextureObject(contextID);
if (textureObject && _textureWidth != 0 && _textureHeight != 0)
{
// bind texture
textureObject->bind();
// compute number of mipmap levels
int width = _textureWidth;
int height = _textureHeight;
int numMipmapLevels = Image::computeNumberOfMipmapLevels(width, height);
// we do not reallocate the level 0, since it was already allocated
width >>= 1;
height >>= 1;
for( GLsizei k = 1; k < numMipmapLevels && (width || height); k++)
{
if (width == 0)
width = 1;
if (height == 0)
height = 1;
glTexImage2D( GL_TEXTURE_2D, k, _internalFormat,
width, height, _borderWidth,
_sourceFormat ? _sourceFormat : _internalFormat,
_sourceType ? _sourceType : GL_UNSIGNED_BYTE, NULL);
width >>= 1;
height >>= 1;
}
// inform state that this texture is the current one bound.
state.haveAppliedTextureAttribute(state.getActiveTextureUnit(), this);
}
}
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