.\"Copyright 2010 (c) EPFL
.TH DTK_UPDATE_SCREEN 3 2010 "EPFL" "Draw Toolkit manual"
.SH NAME
dtk_update_screen, dtk_clear_screen, dtk_bgcolor - screen buffer manipulation
.SH SYNOPSIS
.LP
.B #include <drawtk.h>
.sp
.BI "void dtk_update_screen(dtk_hwnd " wnd ");"
.br
.BI "void dtk_clear_screen(dtk_hwnd " wnd ");"
.br
.BI "void dtk_bgcolor(float *" bgcolor ");"
.br
.SH DESCRIPTION
.LP
\fBdtk_bgcolor\fP() set \fIbgcolor\fP as the background color of the current
rendering context. \fIbgcolor\fP should point to an array of 4 float
corresponding to an normalized RGBA value. If unspecified, the background color
is black.
.LP
\fBdtk_clear_screen\fP() fills the frame buffer with the background color of
the window \fIwnd\fP.
.LP
\fBdtk_update_screen\fP() swaps the front and back frame buffers of the window
\fIwnd\fP. 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
\fBdtk_update_screen\fP() 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 \fBdtk_clear_screen\fP() after an
update of the screen.
.SH "RETURN VALUE"
.LP
These functions return no value.
.SH "SEE ALSO"
.BR