GLRenderTarget Class Reference

#include <GLRenderTarget.h>

Inheritance diagram for GLRenderTarget:

List of all members.

---

Detailed Description

A render target.

This is a texture that can be written to and then bound later for use as a normal texture.

Definition at line 18 of file GLRenderTarget.h.

Public Member Functions
virtual void	bind () const
	Bind this texture.
uint	height () const
	Return the height of the texture.
uint	id () const
	Return the texture ID.
virtual boolean	isValid () const
	Is this a valid texture?
const char *	name () const
	Get the name.
void	prepare () const
	Bind the target.
virtual uint	type () const
	Get the type, e.g. GL_TEXTURE_2D.
void	upload () const
	Copy the framebuffer.
uint	width () const
	Return the width of the texture.
Static Public Member Functions
static GLRenderTarget *	Create (const std::string &szName, uint width, uint height, uint channels)
	Create a render target.
static void	SetDefaultTarget ()
	Set the default target.
Protected Member Functions
	GLRenderTarget (const char *szName, uint ID, uint CBuf, uint DBuf, uint W, uint H)
	Constructor.
virtual	~GLRenderTarget ()
	Destructor.
Static Protected Member Functions
static uint	GetFormat (uint bpp)
	Get the format.
static byte *	LoadImageData (const std::string &szName, uint &width, uint &height, uint &bytespp)
	Load image data.
Protected Attributes
uint	m_ColourBuffer
	The colour and depth buffer IDs.
uint	m_DepthBuffer
uint	m_Height
uint	m_ID
	The texture ID.
std::string	m_Name
	The name.
uint	m_Width

---

Member Function Documentation

GLRenderTarget * GLRenderTarget::Create	(	const std::string &	szName,
		uint	width,
		uint	height,
		uint	channels
	)			[static]

Create a render target.

Use GL_DEPTH_COMPONENT in channels and type for shadow maps

Definition at line 26 of file GLRenderTarget.cpp.

References GLRenderTarget(), SetDefaultTarget(), and IGLTexture::type().

Referenced by GLSpotLight::createShadowMaps(), and Logic::Logic().

{
    uint ID = 0;
    uint ColourBuffer = 0;
    uint DepthBuffer = 0;
    
#ifdef NO_FRAMEBUFFER_OBJS

    // If the channels flag is > 4, then we should have a special 
    // flag in type. (Thanks to GameTutorials.com for this)
    uint type = GL_RGBA;
    uint bytespp = channels;
    switch ( channels )
    {
    case 1: type = GL_LUMINANCE; break;
    case 2: type = GL_LUMINANCE_ALPHA; break;
    case 3: type = GL_RGB; break;
    case 4: type = GL_RGBA; break;
    default:
        type = channels;
        bytespp = 1;
        break;
    }
    
    // Create the buffer
    byte * tex = new byte[width * height * bytespp];
    if ( !tex )
    {
        LOG( szName.c_str(), "Failed to create RTT buffer" );
        return 0;
    }
    
    // Generate a texture
    glGenTextures( 1, &ID );

    // Bind it
    glBindTexture( GL_TEXTURE_2D, ID );

    // Create the image
    glTexImage2D( GL_TEXTURE_2D, 0, channels, width, height, 0, type, GL_UNSIGNED_BYTE, tex );
    
    // Set the parameters
    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
    glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP );
    glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP );

    // glTexParameteri( GL_TEXTURE_2D, GL_DEPTH_TEXTURE_MODE_ARB, GL_LUMINANCE );

    // Delete the array
    delete [] tex;
    
    LOG( "RTT", "Created target %s", szName.c_str() );

#else

    // Create the colour buffer
    glGenFramebuffersEXT( 1, &ColourBuffer );
    
    // Create a depth buffer
    glGenRenderbuffersEXT( 1, &DepthBuffer );
    
    // Create a texture for our colour buffer
    glGenTextures( 1, &ID );
    
    // Bind the colour buffer so we can set our texture parameters
    glBindFramebufferEXT( GL_FRAMEBUFFER_EXT, ColourBuffer );

    // Bind the texture
    glBindTexture( GL_TEXTURE_2D, ID );
    
    // Set the filtering level
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    
    // Set the texture parameters
    glTexImage2D(GL_TEXTURE_2D, 0, channels, width, height, 0, type, GL_INT, 0 );
    
    // Attach the framebuffer to the texture
    glFramebufferTexture2DEXT( GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, ID, 0);
    
    // Bind the depth buffer
    glBindRenderbufferEXT( GL_RENDERBUFFER_EXT, DepthBuffer );
    
    // Set the storage type
    glRenderbufferStorageEXT( GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT24, width, height );
    
    // Bind the buffer to the framebuffer
    glFramebufferRenderbufferEXT( GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, DepthBuffer );
    
    // Check the status
    if ( glCheckFramebufferStatusEXT( GL_FRAMEBUFFER_EXT ) != GL_FRAMEBUFFER_COMPLETE_EXT )
    {
        LOG( "RT", "Couldn't construct full framebuffer of size %dx%d", width, height );
        return 0;
    }
    
    LOG( "RTT", "Constructed FBO target %s", szName.c_str() );
    
#endif

    // Set the default target
    SetDefaultTarget();

    // Create the target
    return new GLRenderTarget( szName.c_str(), ID, ColourBuffer, DepthBuffer, width, height );
}

---

The documentation for this class was generated from the following files:

• GLRenderTarget.h
• GLRenderTarget.cpp

---