glRenderbufferStorage example c c++ java objc

Name

glRenderbufferStorage — establish data storage, format and dimensions of a renderbuffer object's image

C Specification

void glRenderbufferStorage(	GLenum	target,
	GLenum	internalformat,
	GLsizei	width,
	GLsizei	height);

Parameters

target

Specifies a binding to which the target of the allocation and must be GL_RENDERBUFFER.

internalformat

Specifies the internal format to use for the renderbuffer object's image.

width

Specifies the width of the renderbuffer, in pixels.

height

Specifies the height of the renderbuffer, in pixels.

Description

glRenderbufferStorage is equivalent to calling glRenderbufferStorageMultisample with the samples set to zero.
The target of the operation, specified by target must be GL_RENDERBUFFER. internalformat specifies the internal format to be used for the renderbuffer object's storage and must be a color-renderable, depth-renderable, or stencil-renderable format. width and height are the dimensions, in pixels, of the renderbuffer. Both width and height must be less than or equal to the value of GL_MAX_RENDERBUFFER_SIZE.
Upon success, glRenderbufferStorage deletes any existing data store for the renderbuffer image and the contents of the data store after calling glRenderbufferStorage are undefined.

Errors

GL_INVALID_ENUM is generated if target is not GL_RENDERBUFFER.
GL_INVALID_VALUE is generated if either of width or height is negative, or greater than the value of GL_MAX_RENDERBUFFER_SIZE.
GL_INVALID_ENUM is generated if internalformat is not a color-renderable, depth-renderable, or stencil-renderable format.
GL_OUT_OF_MEMORY is generated if the GL is unable to create a data store of the requested size.

See Also

glGenRenderbuffers, glBindRenderbuffer, glRenderbufferStorageMultisample, glFramebufferRenderbuffer, glDeleteRenderbuffers

Copyright

Copyright © 2010 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.

Example of glRenderbufferStorage

// This function does any needed initialization on the rendering

// context. 

void SetupRC()

{

    fprintf(stdout, "FBO Draw Buffers Demo\n\n");

    // Make sure required functionality is available: cube maps, auto mip gen, etc.

    if (!GLEE_VERSION_1_4)

    {

        fprintf(stderr, "OpenGL 1.4 is not available!\n");

        Sleep(2000);

        exit(0);

    }

    if (GLEE_ARB_texture_non_power_of_two)

    {

        npotTexturesAvailable = GL_TRUE;

    }

    else

    {

        fprintf(stderr, "GL_ARB_texture_non_power_of_two extension is not available!\n");

        fprintf(stderr, "Framebuffer effects will be lower resolution (lower quality).\n\n");

    }

    if (!GLEE_EXT_framebuffer_object)

    {

        fprintf(stderr, "GL_EXT_framebuffer_object extension is unavailable!\n");

        Sleep(2000);

        exit(0);

    }

    // we'll use up to 4 render targets if they're available

    glGetIntegerv(GL_MAX_DRAW_BUFFERS, &maxDrawBuffers);

    glGetIntegerv(GL_MAX_COLOR_ATTACHMENTS_EXT, &maxColorAttachments);

    glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &maxTexUnits);

    maxDrawBuffers = (maxDrawBuffers > maxColorAttachments) ? maxColorAttachments : maxDrawBuffers;

    maxDrawBuffers = (maxDrawBuffers > (maxTexUnits-1)) ? (maxTexUnits-1) : maxDrawBuffers;

    maxDrawBuffers = (maxDrawBuffers > 4) ? 4 : maxDrawBuffers;

    if (((!GLEE_ARB_draw_buffers || !GLEE_ARB_fragment_shader || !GLEE_ARB_shader_objects) 

        && !GLEE_VERSION_2_0) || (maxDrawBuffers != 4))

    {

        fprintf(stderr, "Support for at least 4 draw buffers is unavailable!\n");

        Sleep(2000);

        exit(0);

    }

    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxTexSize);

    glGetIntegerv(GL_MAX_RENDERBUFFER_SIZE_EXT, &maxRenderbufferSize);

    maxTexSize = (maxRenderbufferSize > maxTexSize) ? maxTexSize : maxRenderbufferSize;

    fprintf(stdout, "Controls:\n");

    fprintf(stdout, "\tRight-click for menu\n\n");

    fprintf(stdout, "\tx/X\t\tMove +/- in x direction\n");

    fprintf(stdout, "\ty/Y\t\tMove +/- in y direction\n");

    fprintf(stdout, "\tz/Z\t\tMove +/- in z direction\n\n");

    fprintf(stdout, "\td/D\t\tToggle use of draw buffers\n\n");

    fprintf(stdout, "\tq\t\tExit demo\n\n");

    

    // Black background

    glClearColor(0.0f, 0.0f, 0.0f, 1.0f );

    // Hidden surface removal

    glEnable(GL_DEPTH_TEST);

    glDepthFunc(GL_LEQUAL);

    // Set up some lighting state that never changes

    glShadeModel(GL_SMOOTH);

    glLightModeli(GL_LIGHT_MODEL_LOCAL_VIEWER, 1);

    glLightfv(GL_LIGHT0, GL_AMBIENT, ambientLight);

    glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuseLight);

    glLightfv(GL_LIGHT0, GL_SPECULAR, specularLight);

    glLightfv(GL_LIGHT0, GL_POSITION, lightPos);

    glMaterialfv(GL_FRONT, GL_SPECULAR, specularLight);

    glMateriali(GL_FRONT, GL_SHININESS, 128);

    glEnable(GL_LIGHTING);

    glEnable(GL_COLOR_MATERIAL);

    glEnable(GL_NORMALIZE);

    glEnable(GL_LIGHT0);

    // Set up textures & shaders

    SetupTextures();

    SetupShaders();

    // Set up some renderbuffer state

    glGenRenderbuffersEXT(1, &renderbufferID);

    glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, renderbufferID);

    glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT32, fboWidth, fboHeight);

    glGenFramebuffersEXT(2, framebufferID);

    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, framebufferID[0]);

    glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, renderbufferID);

    glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, renderTextureID[0], 0);

    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, framebufferID[1]);

    for (int i = 0; i < maxDrawBuffers; i++)

    {

        glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT + i, GL_TEXTURE_2D, renderTextureID[i+1], 0);

    }

    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);

}