DTK_UPDATE_SCREEN(3) Draw Toolkit manual DTK_UPDATE_SCREEN(3)NAME
dtk_update_screen, dtk_clear_screen, dtk_bgcolor - screen buffer manipulation
SYNOPSIS
#include <drawtk.h>
void dtk_update_screen(dtk_hwnd wnd);
void dtk_clear_screen(dtk_hwnd wnd);
void dtk_bgcolor(float *bgcolor);
DESCRIPTION
dtk_bgcolor() set bgcolor as the background color of the current rendering context. bgcolor should point to an array of 4 float correspond-
ing to an normalized RGBA value. If unspecified, the background color is black.
dtk_clear_screen() fills the frame buffer with the background color of the window wnd.
dtk_update_screen() swaps the front and back frame buffers of the window wnd. Rendering is performed through double buffering, i.e. the
draws are rendered on the back buffer which will be displayed on screen when a call to dtk_update_screen() will be performed. After an
update, the content of the back buffer is undefined. So if the rendered scene does not rewrite the whole frame buffer, it is safer to call
dtk_clear_screen() after an update of the screen.
RETURN VALUE
These functions return no value.
SEE ALSO EPFL 2010 DTK_UPDATE_SCREEN(3)
Check Out this Related Man Page
GLDRAWBUFFER(3G) OpenGL Manual GLDRAWBUFFER(3G)NAME
glDrawBuffer - specify which color buffers are to be drawn into
C SPECIFICATION
void glDrawBuffer(GLenum mode);
PARAMETERS
mode
Specifies up to four color buffers to be drawn into. Symbolic constants GL_NONE, GL_FRONT_LEFT, GL_FRONT_RIGHT, GL_BACK_LEFT,
GL_BACK_RIGHT, GL_FRONT, GL_BACK, GL_LEFT, GL_RIGHT, and GL_FRONT_AND_BACK are accepted. The initial value is GL_FRONT for
single-buffered contexts, and GL_BACK for double-buffered contexts.
DESCRIPTION
When colors are written to the frame buffer, they are written into the color buffers specified by glDrawBuffer. The specifications are as
follows:
GL_NONE
No color buffers are written.
GL_FRONT_LEFT
Only the front left color buffer is written.
GL_FRONT_RIGHT
Only the front right color buffer is written.
GL_BACK_LEFT
Only the back left color buffer is written.
GL_BACK_RIGHT
Only the back right color buffer is written.
GL_FRONT
Only the front left and front right color buffers are written. If there is no front right color buffer, only the front left color
buffer is written.
GL_BACK
Only the back left and back right color buffers are written. If there is no back right color buffer, only the back left color buffer is
written.
GL_LEFT
Only the front left and back left color buffers are written. If there is no back left color buffer, only the front left color buffer is
written.
GL_RIGHT
Only the front right and back right color buffers are written. If there is no back right color buffer, only the front right color
buffer is written.
GL_FRONT_AND_BACK
All the front and back color buffers (front left, front right, back left, back right) are written. If there are no back color buffers,
only the front left and front right color buffers are written. If there are no right color buffers, only the front left and back left
color buffers are written. If there are no right or back color buffers, only the front left color buffer is written.
If more than one color buffer is selected for drawing, then blending or logical operations are computed and applied independently for each
color buffer and can produce different results in each buffer.
Monoscopic contexts include only left buffers, and stereoscopic contexts include both left and right buffers. Likewise, single-buffered
contexts include only front buffers, and double-buffered contexts include both front and back buffers. The context is selected at GL
initialization.
ERRORS
GL_INVALID_ENUM is generated if mode is not an accepted value.
GL_INVALID_OPERATION is generated if none of the buffers indicated by mode exists.
ASSOCIATED GETS
glGet() with argument GL_DRAW_BUFFER
SEE ALSO
glBlendFunc(), glColorMask(), glDrawBuffers(), glLogicOp(), glReadBuffer()
COPYRIGHT
Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see
http://oss.sgi.com/projects/FreeB/.
AUTHORS
opengl.org
opengl.org 06/10/2014 GLDRAWBUFFER(3G)