First draft of new general OpenGL Buffer abstraction

include/ACGL/OpenGL/Objects/Buffer.hh

+////////////////////////////////////////////////////////////////////////////////
+// Copyright (c) 2011, Computer Graphics Group RWTH Aachen University         //
+// All rights reserved.                                                       //
+////////////////////////////////////////////////////////////////////////////////
+
+#ifndef ACGL_OPENGL_OBJECTS_BUFFER_HH
+#define ACGL_OPENGL_OBJECTS_BUFFER_HH
+
+/*
+ * A generic OpenGL Buffer Object
+ *
+ * Mostly an OpenGL Buffer Wrapper: names of OpenGL calls are stripped of the
+ * 'gl' and 'Buffer' tokens and setters got a 'set' prefix.
+ *
+ * Calls that give the target the buffer should get bound to have an alternative
+ * call that uses the last used or set target.
+ *
+ * Note: Most methods will bind this buffer!
+ */
+
+#include <ACGL/ACGL.hh>
+
+#include <ACGL/Base/Macros.hh>
+#include <ACGL/OpenGL/GL.hh>
+#include <ACGL/OpenGL/Tools.hh>
+
+#include <string>
+#include <vector>
+#include <tr1/memory>
+
+namespace ACGL{
+namespace OpenGL{
+
+class Buffer
+{
+    ACGL_NOT_COPYABLE(Buffer)
+
+    // ========================================================================================================= \/
+    // ============================================================================================ CONSTRUCTORS \/
+    // ========================================================================================================= \/
+public:
+    Buffer(void) :   mLastTarget(GL_INVALID_VALUE), mObjectName(0)
+    {
+        glGenBuffers(1, &mObjectName);
+    }
+
+    virtual ~Buffer(void)
+    {
+        // buffer 0 will get ignored by OpenGL
+        glDeleteBuffers(1, &mObjectName);
+    }
+
+    // ==================================================================================================== \/
+    // ============================================================================================ GETTERS \/
+    // ==================================================================================================== \/
+public:
+    inline GLuint operator()    (void) const { return mObjectName; }
+    inline GLuint getObjectName (void) const { return mObjectName; }
+    inline bool   isValid       (void) const { return glIsBuffer( mObjectName ); }
+
+private:
+    inline GLint getParameter( GLenum _parameter ) {
+        bind( mLastTarget );
+        GLint value;
+        glGetBufferParameteriv( mLastTarget, _parameter, &value );
+        return value;
+    }
+
+#if (ACGL_OPENGL_VERSION >= 32)
+    inline GLint64 getParameter64( GLenum _parameter ) {
+        bind( mLastTarget );
+        GLint64 value;
+        glGetBufferParameteri64v( mLastTarget, _parameter, &value );
+        return value;
+    }
+
+    //! not side effect free! will bind this buffer to it's last target!
+    //! caching of these values on RAM could be a good idea if needed very often!
+    inline GLint64   getSize()        { return             getParameter64( GL_BUFFER_SIZE         ); }
+    inline GLint64   getMapOffset()   { return             getParameter64( GL_BUFFER_MAP_OFFSET   ); }
+    inline GLint64   getMapLength()   { return             getParameter64( GL_BUFFER_MAP_LENGTH   ); }
+#else // OpenGL pre 3.2:
+    inline GLint     getSize()        { return             getParameter  ( GL_BUFFER_SIZE         ); }
+    inline GLint     getMapOffset()   { return             getParameter  ( GL_BUFFER_MAP_OFFSET   ); }
+    inline GLint     getMapLength()   { return             getParameter  ( GL_BUFFER_MAP_LENGTH   ); }
+#endif // OpenGL >= 3.2
+    inline GLenum    getUsage()       { return (GLenum)    getParameter  ( GL_BUFFER_USAGE        ); }
+    inline GLenum    getAccess()      { return (GLenum)    getParameter  ( GL_BUFFER_ACCESS       ); }
+    inline GLint     getAccessFlags() { return (GLint)     getParameter  ( GL_BUFFER_ACCESS_FLAGS ); }
+    inline GLboolean isMapped()       { return (GLboolean) getParameter  ( GL_BUFFER_MAPPED       ); }
+
+
+
+    // ===================================================================================================== \/
+    // ============================================================================================ WRAPPERS \/
+    // ===================================================================================================== \/
+public:
+    //! Bind this buffer
+    inline void bind( GLenum _target )
+    {
+        glBindBuffer( _target, mObjectName );
+        openGLRareError();
+        mLastTarget = _target;
+    }
+
+    //! Bind this buffer to its last target
+    inline void bind()
+    {
+        glBindBuffer( mLastTarget, mObjectName );
+        openGLRareError();
+    }
+
+    //! Set data for this buffer. Use only to init the buffer!
+    //! Note: The function is not const, because it changes the corresponding GPU data
+    inline void setData( GLenum _target, GLsizeiptr _size, const GLvoid *_pData = NULL, GLenum _usage = GL_STATIC_DRAW ) {
+        bind( _target );
+        glBufferData( _target, _size, _pData, _usage );
+        openGLRareError();
+    }
+
+    //! Set data for this buffer at the last used target. Use only to init the buffer!
+    inline void setData( GLsizeiptr _size, const GLvoid *_pData = NULL, GLenum _usage = GL_STATIC_DRAW ) {
+        setData( mLastTarget, _size, _pData, _usage );
+    }
+
+    //! Use this to modify the buffer
+    inline void setSubData( GLenum _target, GLintptr _offset,
+                            GLsizeiptr _size, const GLvoid *_pData ) {
+        bind( _target );
+        glBufferSubData( _target, _offset, _size, _pData );
+        openGLRareError();
+    }
+
+    //! Use this to modify the buffer
+    inline void setSubData( GLintptr _offset, GLsizeiptr _size, const GLvoid *_pData ) {
+        setSubData( mLastTarget, _offset, _size, _pData );
+    }
+
+
+#if (ACGL_OPENGL_VERSION >= 30)
+    /** Map a part of the buffer to client memory
+     * _offset & _length are values in bytes relative to the buffer
+     * _access must contain one (or both) of:
+     *      GL_MAP_READ_BIT and GL_MAP_WRITE_BIT
+     *  and optionally:
+     *      GL_MAP_INVALIDATE_RANGE_BIT GL_MAP_INVALIDATE_BUFFER_BIT
+     *      GL_MAP_FLUSH_EXPLICIT_BIT GL_MAP_UNSYNCHRONIZED_BIT
+     */
+    GLvoid *mapRange( GLenum _target, GLintptr _offset, GLsizeiptr _length, GLbitfield _access ) {
+        bind( _target );
+        GLvoid *ret = glMapBufferRange( _target, _offset, _length, _access );
+        openGLRareError();
+        return ret;
+    }
+
+    inline GLvoid *mapRange( GLintptr _offset, GLsizeiptr _length, GLbitfield _access ) {
+        return mapRange( mLastTarget, _offset, _length, _access );
+    }
+
+    /**
+     * Spec:
+     * If a buffer is mapped with the GL_MAP_FLUSH_EXPLICIT_BIT flag, modifications
+     * to the mapped range may be indicated by calling this.
+     * _offset and _length indicate a modified subrange of the mapping, in byte. The specified
+     * subrange to flush is relative to the start of the currently mapped range of buffer.
+     * This can be called multiple times to indicate distinct subranges
+     * of the mapping which require flushing.
+     */
+    void flushMappedRange( GLenum _target, GLsizeiptr _offset, GLsizeiptr _length ) {
+        bind( _target );
+        glFlushMappedBufferRange( _target, _offset, _length );
+        openGLRareError();
+    }
+
+    inline void flushMappedRange( GLintptr _offset, GLsizeiptr _length ) {
+        flushMappedRange( mLastTarget, _offset, _length );
+    }
+
+    // TODO: bindBufferRange
+    // TODO: bindBufferBase
+#endif // OpenGL >= 3.0
+
+    //! Maps the whole buffer, if using GL 3+, better use mapRange!
+    //! _access is GL_READ_ONLY GL_WRITE_ONLY or GL_READ_WRITE
+    GLvoid *map( GLenum _target, GLenum _access ) {
+        bind( _target );
+        GLvoid *ret = glMapBuffer( _target, _access );
+        openGLRareError();
+        return ret;
+    }
+    inline GLvoid *map( GLenum _access ) {
+        return map( mLastTarget, _access );
+    }
+
+    GLboolean unmap( GLenum _target ) {
+        bind( _target );
+        GLboolean ret = glUnmapBuffer( _target );
+        openGLRareError();
+        return ret;
+    }
+
+    inline GLboolean unmap() {
+        return unmap( mLastTarget );
+    }
+
+    // TODO: CopyBufferSubData
+
+    /**
+     * _target must be one of:
+        GL_ARRAY_BUFFER
+        GL_ATOMIC_COUNTER_BUFFER
+        GL_COPY_READ_BUFFER
+        GL_COPY_WRITE_BUFFER
+        GL_DRAW_INDIRECT_BUFFER
+        GL_ELEMENT_ARRAY_BUFFER
+        GL_PIXEL_PACK_BUFFER
+        GL_PIXEL_UNPACK_BUFFER
+        GL_TEXTURE_BUFFER
+        GL_TRANSFORM_FEEDBACK_BUFFER
+        GL_UNIFORM_BUFFER
+     * Can be changed at any time. Will get changed if a _target gets specified at any call.
+     */
+    inline void setTarget( GLenum _target ) { mLastTarget = _target; }
+
+    // =================================================================================================== \/
+    // ============================================================================================ FIELDS \/
+    // =================================================================================================== \/
+protected:
+    GLenum       mLastTarget;
+    GLuint       mObjectName;
+};
+
+ACGL_SHARED_TYPEDEF(ArrayBuffer)
+
+} // OpenGL
+} // ACGL
+
+#endif // ACGL_OPENGL_OBJECTS_BUFFER_HH