[libcvd-members] libcvd/cvd gl_helpers.h

[Gerhard Reitmayr]

CVSROOT:        /cvsroot/libcvd
Module name:    libcvd
Changes by:     Gerhard Reitmayr <gerhard>      07/05/05 13:12:34

Modified files:
        cvd            : gl_helpers.h 

Log message:
        more texture support, a simple texture id management facility based on 
images

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/libcvd/cvd/gl_helpers.h?cvsroot=libcvd&r1=1.28&r2=1.29

Patches:
Index: gl_helpers.h
===================================================================
RCS file: /cvsroot/libcvd/libcvd/cvd/gl_helpers.h,v
retrieving revision 1.28
retrieving revision 1.29
diff -u -b -r1.28 -r1.29
--- gl_helpers.h        14 Dec 2006 00:45:31 -0000      1.28
+++ gl_helpers.h        5 May 2007 13:12:34 -0000       1.29
@@ -22,7 +22,7 @@
 #define CVD_GL_HELPERS_H
 
 #include <iostream>
-#include <vector>
+#include <map>
 
 #include <cvd/image_ref.h>
 #include <cvd/image.h>
@@ -372,10 +372,10 @@
        /// glVertex helpers defined in this header file.
        /// @param list the list of vertices
        /// @ingroup gGL
-       template<class T> inline void glVertex( const std::vector<T> & list )
+       template<class C> inline void glVertex( const C & list )
        {
-               for(unsigned int i=0; i < list.size(); i++)
-                       glVertex(list[i]);
+               for(typename C::const_iterator v = list.begin(); v != 
list.end(); ++v)
+                       glVertex(*v);
        }
 
        /// Set the new colour to the red, green, blue components given
@@ -444,16 +444,6 @@
                ::glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
        }
 
-       /// Sets an image as a texture sub region.
-       /// note the reordering of the various parameters to make better use of 
default parameters
-       /// @param i the image to set as texture
-       /// @ingroup gGL
-       template<class C> inline void glTexSubImage2D( const BasicImage<C> &i, 
GLint xoffset = 0, GLint yoffset = 0, GLenum target = GL_TEXTURE_2D, GLint 
level = 0)
-       {
-               ::glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-               ::glTexSubImage2D(target, level, xoffset, yoffset, i.size().x, 
i.size().y, gl::data<C>::format, gl::data<C>::type, i.data());
-       }
-
        /// Read the current image from the colour buffer specified by 
glReadBuffer
        /// @param i The image to write the image data into. This must already 
be initialised to be an BasicImage (or Image) of the right size.
        /// @param origin The window co-ordinate of the first pixel to be read 
from the frame buffer
@@ -474,6 +464,79 @@
                return i;
        }
 
+       /// Sets an image as a texture sub region.
+       /// note the reordering of the various parameters to make better use of 
default parameters
+       /// @param i the image to set as texture
+       /// @ingroup gGL
+       template<class C> inline void glTexSubImage2D( const BasicImage<C> &i, 
GLint xoffset = 0, GLint yoffset = 0, GLenum target = GL_TEXTURE_2D, GLint 
level = 0)
+       {
+               ::glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+               ::glTexSubImage2D(target, level, xoffset, yoffset, i.size().x, 
i.size().y, gl::data<C>::format, gl::data<C>::type, i.data());
+       }
+
+       /// Sets an image as a texture.
+       /// note the reordering of the various parameters to make better use of 
default parameters
+       /// @param i the image to set as texture
+       /// @ingroup gGL
+       template<class C> inline void glTexImage2D( const BasicImage<C> &i, 
GLint border = 0, GLenum target = GL_TEXTURE_2D, GLint level = 0)
+       {
+               ::glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+               ::glTexImage2D(target, level, gl::data<C>::format, i.size().x, 
i.size().y, border, gl::data<C>::format, gl::data<C>::type, i.data());
+       }
+
+       #ifndef DOXYGEN_IGNORE_INTERNAL
+       /// internal struct to keep the map of the image addresses to texture 
ids
+       template <int LIFT = 1>
+       struct TextureStore {
+               static std::map<const void *, GLuint> texIds;
+
+               template <class C>
+               static void bindTexture(const BasicImage<C> & i){
+                       std::map<const void *, GLuint>::iterator id = 
texIds.find(&i);
+                       if(id != texIds.end()){
+                               glBindTexture(GL_TEXTURE_2D, id->second);
+                       } else{
+                               GLuint newId;
+                               glGenTextures(1, &newId);
+                               texIds[&i] = newId;
+                               glBindTexture(GL_TEXTURE_2D, newId);
+                                       glTexParameteri(GL_TEXTURE_2D, 
GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+                               glTexParameteri(GL_TEXTURE_2D, 
GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+                               glTexImage2D(i);
+                       }
+               }
+
+               template <class C>
+               static void deleteTexture(const BasicImage<C> & i){
+                       std::map<const void *, GLuint>::iterator id = 
texIds.find(&i);
+                       if(id != texIds.end()){
+                               glDeleteTextures(1, &id->second);
+                               texIds.erase(id);
+                       }
+               }
+       };
+
+       template<int LIFT> std::map<const void *, GLuint> 
TextureStore<LIFT>::texIds;
+       #endif
+
+       /// stores an image as a GL texture. The image address
+       /// is used as a token in an internal store of texture ids. It only 
uploads the
+       /// texture automatically upon first use, after that it only rebinds 
the id.
+       /// use glTexImage2D to upload a new texture after this call.
+       /// @param i the image to upload
+       /// @ingroup gGL
+       template<class C> inline void glBindTexture(const BasicImage<C> & i){
+               TextureStore<>::bindTexture(i);
+       }
+
+       /// deletes a texture, frees the underlying texture id and removes the
+       /// images address from the store
+       /// @param i the image to delete
+       /// @ingroup gGL
+       template<class C> inline void glDeleteTextures(const BasicImage<C> & i){
+               TextureStore<>::deleteTexture(i);
+       }
+
     /// Prints the current errors on the gl error stack
     ///@ingroup gGL
     inline void glPrintErrors(void){