FGFS-4.1/OpenSceneGraph
4
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Added support for creating a 3D Image from an image list.

Browse Source 
Added support for reading a list of images in the Present3D <volume> tag.
This commit is contained in:
Robert Osfield
2011-06-08 16:10:46 +00:00
parent ebc3c295a7
commit 86439123b4
4 changed files with 313 additions and 42 deletions
Download Patch File Download Diff File Expand all files Collapse all files

123
examples/osgvolume/osgvolume.cpp
View File

@@ -70,8 +70,6 @@
#include <osgVolume/RayTracedTechnique>
#include <osgVolume/FixedFunctionTechnique>
typedef std::vector< osg::ref_ptr<osg::Image> > ImageList;
enum ShadingModel
{
Standard,
@@ -86,6 +84,86 @@ struct PassThroughTransformFunction
};
void clampToNearestValidPowerOfTwo(int& sizeX, int& sizeY, int& sizeZ, int s_maximumTextureSize, int t_maximumTextureSize, int r_maximumTextureSize)
{
// compute nearest powers of two for each axis.
int s_nearestPowerOfTwo = 1;
while(s_nearestPowerOfTwo<sizeX && s_nearestPowerOfTwo<s_maximumTextureSize) s_nearestPowerOfTwo*=2;
int t_nearestPowerOfTwo = 1;
while(t_nearestPowerOfTwo<sizeY && t_nearestPowerOfTwo<t_maximumTextureSize) t_nearestPowerOfTwo*=2;
int r_nearestPowerOfTwo = 1;
while(r_nearestPowerOfTwo<sizeZ && r_nearestPowerOfTwo<r_maximumTextureSize) r_nearestPowerOfTwo*=2;
sizeX = s_nearestPowerOfTwo;
sizeY = t_nearestPowerOfTwo;
sizeZ = r_nearestPowerOfTwo;
}
#if 1
struct ModulateAlphaByLuminanceOperator
{
ModulateAlphaByLuminanceOperator() {}
inline void luminance(float&) const {}
inline void alpha(float&) const {}
inline void luminance_alpha(float& l,float& a) const { a*= l; }
inline void rgb(float&,float&,float&) const {}
inline void rgba(float& r,float& g,float& b,float& a) const { float l = (r+g+b)*0.3333333; a *= l;}
};
osg::Image* createTexture3D(osg::ImageList& imageList,
unsigned int numComponentsDesired,
int s_maximumTextureSize,
int t_maximumTextureSize,
int r_maximumTextureSize,
bool resizeToPowerOfTwo)
{
GLenum desiredPixelFormat = 0;
bool modulateAlphaByLuminance = false;
if (numComponentsDesired==0)
{
unsigned int maxNumComponents = osg::maximimNumOfComponents(imageList);
if (maxNumComponents==3)
{
desiredPixelFormat = GL_RGBA;
modulateAlphaByLuminance = true;
}
}
else
{
switch(numComponentsDesired)
{
case(1) : desiredPixelFormat = GL_LUMINANCE; break;
case(2) : desiredPixelFormat = GL_LUMINANCE_ALPHA; break;
case(3) : desiredPixelFormat = GL_RGB; break;
case(4) : desiredPixelFormat = GL_RGBA; break;
}
}
osg::ref_ptr<osg::Image> image = osg::createImage3D(imageList,
desiredPixelFormat,
s_maximumTextureSize,
t_maximumTextureSize,
r_maximumTextureSize,
resizeToPowerOfTwo);
if (image.valid())
{
if (modulateAlphaByLuminance)
{
osg::modifyImage(image.get(), ModulateAlphaByLuminanceOperator());
}
return image.release();
}
else
{
return 0;
}
}
#else
struct ProcessRow
{
virtual ~ProcessRow() {}
@@ -435,36 +513,19 @@ struct ProcessRow
};
void clampToNearestValidPowerOfTwo(int& sizeX, int& sizeY, int& sizeZ, int s_maximumTextureSize, int t_maximumTextureSize, int r_maximumTextureSize)
{
// compute nearest powers of two for each axis.
int s_nearestPowerOfTwo = 1;
while(s_nearestPowerOfTwo<sizeX && s_nearestPowerOfTwo<s_maximumTextureSize) s_nearestPowerOfTwo*=2;
int t_nearestPowerOfTwo = 1;
while(t_nearestPowerOfTwo<sizeY && t_nearestPowerOfTwo<t_maximumTextureSize) t_nearestPowerOfTwo*=2;
int r_nearestPowerOfTwo = 1;
while(r_nearestPowerOfTwo<sizeZ && r_nearestPowerOfTwo<r_maximumTextureSize) r_nearestPowerOfTwo*=2;
sizeX = s_nearestPowerOfTwo;
sizeY = t_nearestPowerOfTwo;
sizeZ = r_nearestPowerOfTwo;
}
osg::Image* createTexture3D(ImageList& imageList, ProcessRow& processRow,
osg::Image* createTexture3D(osg::ImageList& imageList,
unsigned int numComponentsDesired,
int s_maximumTextureSize,
int t_maximumTextureSize,
int r_maximumTextureSize,
bool resizeToPowerOfTwo)
{
ProcessRow processRow;
int max_s = 0;
int max_t = 0;
unsigned int max_components = 0;
int total_r = 0;
ImageList::iterator itr;
osg::ImageList::iterator itr;
for(itr=imageList.begin();
itr!=imageList.end();
++itr)
@@ -592,7 +653,7 @@ osg::Image* createTexture3D(ImageList& imageList, ProcessRow& processRow,
}
return image_3d.release();
}
#endif
struct ScaleOperator
{
@@ -769,17 +830,6 @@ enum ColourSpaceOperation
REPLACE_RGB_WITH_LUMINANCE
};
struct ModulateAlphaByLuminanceOperator
{
ModulateAlphaByLuminanceOperator() {}
inline void luminance(float&) const {}
inline void alpha(float&) const {}
inline void luminance_alpha(float& l,float& a) const { a*= l; }
inline void rgb(float&,float&,float&) const {}
inline void rgba(float& r,float& g,float& b,float& a) const { float l = (r+g+b)*0.3333333; a *= l;}
};
struct ModulateAlphaByColourOperator
{
ModulateAlphaByColourOperator(const osg::Vec4& colour):_colour(colour) { _lum = _colour.length(); }
@@ -1256,7 +1306,7 @@ int main( int argc, char **argv )
int images_pos = arguments.find("--images");
if (images_pos>=0)
{
ImageList imageList;
osg::ImageList imageList;
int pos=images_pos+1;
for(;pos<arguments.argc() && !arguments.isOption(pos);++pos)
{
@@ -1291,8 +1341,7 @@ int main( int argc, char **argv )
arguments.remove(images_pos, pos-images_pos);
// pack the textures into a single texture.
ProcessRow processRow;
osg::Image* image = createTexture3D(imageList, processRow, numComponentsDesired, s_maximumTextureSize, t_maximumTextureSize, r_maximumTextureSize, resizeToPowerOfTwo);
osg::Image* image = createTexture3D(imageList, numComponentsDesired, s_maximumTextureSize, t_maximumTextureSize, r_maximumTextureSize, resizeToPowerOfTwo);
if (image)
{
images.push_back(image);