mirror of
https://github.com/fltk/fltk.git
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Updated all links so they work between files.
Revision 1. git-svn-id: file:///fltk/svn/fltk/trunk@219 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
This commit is contained in:
Michael R Sweet
+193
-240
@@ -1,166 +1,134 @@
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<html>
|
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<body>
|
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|
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<hr break>
|
||||
|
||||
<h2><a name="Fl_Gl_Window">class Fl_Gl_Window</a></h2>
|
||||
|
||||
<hr>
|
||||
|
||||
<h3>Class Hierarchy</h3>
|
||||
|
||||
<ul><pre>
|
||||
<a href="#Fl_Widget">Fl_Widget</a>
|
||||
<HTML><BODY>
|
||||
<HR break>
|
||||
<H2><A name=Fl_Gl_Window>class Fl_Gl_Window</A></H2>
|
||||
<HR>
|
||||
<H3>Class Hierarchy</H3>
|
||||
<UL>
|
||||
<PRE>
|
||||
<A href=Fl_Widget.html#Fl_Widget>Fl_Widget</A>
|
||||
|
|
||||
+----<b>Fl_Gl_Window</b>
|
||||
+----<B>Fl_Gl_Window</B>
|
||||
|
|
||||
+----<a href="#Fl_Pack">Fl_Pack</a>, <a href="#Fl_Scroll">Fl_Scroll</a>, <a href="#Fl_Tabs">Fl_Tabs</a>, <a href="#Fl_Tile">Fl_Tile</a>, <a href="#Fl_Window">Fl_Window</a>
|
||||
</pre></ul>
|
||||
|
||||
<h3>Include Files</h3>
|
||||
|
||||
<ul><pre>
|
||||
#include <FL/Fl_Gl_Window.H>
|
||||
</pre></ul>
|
||||
|
||||
<h3>Description</h3>
|
||||
|
||||
The <tt>Fl_Gl_Window</tt> widget sets things up so OpenGL works, and
|
||||
also keeps an OpenGL "context" for that window, so that changes to the
|
||||
lighting and projection may be reused between redraws.
|
||||
</tt>Fl_Gl_Window</tt> also flushes the OpenGL streams and swaps
|
||||
buffers after <tt>draw()</tt> returns.
|
||||
|
||||
<p>OpenGL hardware typically provides some overlay bit planes, which
|
||||
are very useful for drawing UI controls atop your 3D graphics. If the
|
||||
overlay hardware is not provided, FLTK tries to simulate the overlay,
|
||||
This works pretty well if your graphics are double buffered, but not
|
||||
very well for single-buffered.
|
||||
|
||||
<h3>Methods</h3>
|
||||
|
||||
|
||||
<center>
|
||||
<table width=90%>
|
||||
<tr>
|
||||
<td align=left valign=top>
|
||||
<ul>
|
||||
<li><a href="#Fl_Gl_Window.Fl_Gl_Window">Fl_Gl_Window</a>
|
||||
<li><a href="#Fl_Gl_Window.~Fl_Gl_Window">~Fl_Gl_Window</a>
|
||||
<li><a href="#Fl_Gl_Window.can_do">can_do</a>
|
||||
<li><a href="#Fl_Gl_Window.can_do_overlay">can_do_overlay</a>
|
||||
</ul>
|
||||
</td>
|
||||
<td align=left valign=top>
|
||||
<ul>
|
||||
<li><a href="#Fl_Gl_Window.draw">draw</a>
|
||||
<li><a href="#Fl_Gl_Window.draw_overlay">draw_overlay</a>
|
||||
<li><a href="#Fl_Gl_Window.handle">handle</a>
|
||||
</ul>
|
||||
</td>
|
||||
<td align=left valign=top>
|
||||
<ul>
|
||||
<li><a href="#Fl_Gl_Window.hide">hide</a>
|
||||
<li><a href="#Fl_Gl_Window.invalidate">invalidate</a>
|
||||
<li><a href="#Fl_Gl_Window.make_current">make_current</a>
|
||||
</ul>
|
||||
</td>
|
||||
<td align=left valign=top>
|
||||
<ul>
|
||||
<li><a href="#Fl_Gl_Window.make_overlay_current">make_overlay_current</a>
|
||||
<li><a href="#Fl_Gl_Window.mode">mode</a>
|
||||
<li><a href="#Fl_Gl_Window.ortho">ortho</a>
|
||||
</ul>
|
||||
</td>
|
||||
<td align=left valign=top>
|
||||
<ul>
|
||||
<li><a href="#Fl_Gl_Window.redraw_overlay">redraw_overlay</a>
|
||||
<li><a href="#Fl_Gl_Window.swap_buffers">swap_buffers</a>
|
||||
<li><a href="#Fl_Gl_Window.valid">valid</a>
|
||||
</ul>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
</center>
|
||||
|
||||
<h4><a name="Fl_Gl_Window.Fl_Gl_Window">Fl_Gl_Window::Fl_Gl_Window(int x, int y, int w, int h, const char *label = 0)</a></h4>
|
||||
|
||||
Creates a new <tt>Fl_Gl_Window</tt> widget using the given position, size, and
|
||||
label string. The default boxtype is <tt>FL_NO_BOX</tt>. The default mode is
|
||||
<tt>FL_RGB|FL_DOUBLE|FL_DEPTH</tt>.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.~Fl_Gl_Window">virtual Fl_Gl_Window::~Fl_Gl_Window()</a></h4>
|
||||
|
||||
The destructor removes the widget and destroys the OpenGL context associated
|
||||
with it.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.draw">virtual void Fl_Gl_Window::draw(void)</a></h4>
|
||||
|
||||
<tt>Fl_Gl_Window::draw()</tt> is a pure virtual method. You must
|
||||
subclass <tt>Fl_Gl_Window</tt> and provide an implementation for
|
||||
<tt>draw()</tt>. You may also provide an implementation of
|
||||
draw_overlay() if you want to draw into the overlay planes. You can
|
||||
avoid reinitializing the viewport and lights and other things by
|
||||
checking <tt>valid()</tt> at the start of <tt>draw()</tt> and only
|
||||
doing the initialization if it is false.
|
||||
|
||||
<p>The <tt>draw()</tt> method can <i>only</i> use OpenGL calls. Do not
|
||||
attempt to call X, any of the functions in <FL/fl_draw.H>, or
|
||||
<tt>glX</tt> directly. Do not call <tt>gl_start()</tt> or
|
||||
<tt>gl_finish()</tt>.
|
||||
|
||||
<p>If double-buffering is enabled in the window, the back and front buffers
|
||||
are swapped after this function is completed.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.mode">const int Fl_Gl_Window::mode() const<br>
|
||||
int Fl_Gl_Window::mode(int m)</a></h4>
|
||||
|
||||
Set or change the OpenGL capabilites of the window. The value can be
|
||||
any of the following OR'd together:
|
||||
|
||||
<ul>
|
||||
<li><tt>FL_RGB</tt> - RGB color (not indexed)
|
||||
<li><tt>FL_RGB8</tt> - RGB color with at least 8 bits of each color
|
||||
<li><tt>FL_INDEX</tt> - Indexed mode
|
||||
<li><tt>FL_SINGLE</tt> - not double buffered
|
||||
<li><tt>FL_DOUBLE</tt> - double buffered
|
||||
<li><tt>FL_ACCUM</tt> - accumulation buffer
|
||||
<li><tt>FL_ALPHA</tt> - alpha channel in color
|
||||
<li><tt>FL_DEPTH</tt> - depth buffer
|
||||
<li><tt>FL_STENCIL</tt> - stencil buffer
|
||||
<li><tt>FL_MULTISAMPLE</tt> - multisample antialiasing
|
||||
</ul>
|
||||
|
||||
<tt>FL_RGB</tt> and <tt>FL_SINGLE</tt> have a value of zero, so they are
|
||||
"on" unless you give <tt>FL_INDEX</tt> or <tt>FL_DOUBLE</tt>.
|
||||
|
||||
<p>If the desired combination cannot be done, FLTK will try turning off
|
||||
<tt>FL_MULTISAMPLE</tt>. If this also fails the <tt>show()</tt> will call
|
||||
<tt>Fl::error()</tt> and not show the window.
|
||||
|
||||
<p>You can change the mode while the window is displayed. This
|
||||
is most useful for turning double-buffering on and off. Under
|
||||
X this will cause the old X window to be destroyed and a new one to be
|
||||
created. If this is a top-level window this will unfortunately also
|
||||
cause the window to blink, raise to the top, and be de-iconized, and
|
||||
the <tt>xid()</tt> will change, possibly breaking other code. It is best to
|
||||
make the GL window a child of another window if you wish to do this!
|
||||
|
||||
<h4><a name="Fl_Gl_Window.can_do">static int Fl_Gl_Window::can_do(int)<br>
|
||||
int Fl_Gl_Window::can_do() const</a></h4>
|
||||
|
||||
Returns non-zero if the hardware supports the given or current OpenGL mode.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.valid">char Fl_Gl_Window::valid() const<br>
|
||||
void Fl_Gl_Window::valid(char i)</a></h4>
|
||||
|
||||
<tt>Fl_Gl_Window::valid()</tt> is turned off when FLTK creates a
|
||||
new context for this window or when the window resizes, and is turned
|
||||
on <i>after</i> <tt>draw()</tt> is called. You can use this inside your <tt>draw()</tt>
|
||||
method to avoid unneccessarily initializing the OpenGL context. Just
|
||||
do this:
|
||||
|
||||
<ul><pre>
|
||||
+----<A href=Fl_Pack.html#Fl_Pack>Fl_Pack</A>, <A href=Fl_Scroll.html#Fl_Scroll>Fl_Scroll</A>, <A href=Fl_Tabs.html#Fl_Tabs>Fl_Tabs</A>, <A href=Fl_Tile.html#Fl_Tile>Fl_Tile</A>, <A href=Fl_Window.html#Fl_Window>Fl_Window</A>
|
||||
</PRE>
|
||||
</UL>
|
||||
<H3>Include Files</H3>
|
||||
<UL>
|
||||
<PRE>
|
||||
#include <FL/Fl_Gl_Window.H>
|
||||
</PRE>
|
||||
</UL>
|
||||
<H3>Description</H3>
|
||||
The <TT>Fl_Gl_Window</TT> widget sets things up so OpenGL works, and
|
||||
also keeps an OpenGL "context" for that window, so that changes to the
|
||||
lighting and projection may be reused between redraws. Fl_Gl_Window
|
||||
also flushes the OpenGL streams and swaps buffers after <TT>draw()</TT>
|
||||
returns.
|
||||
<P>OpenGL hardware typically provides some overlay bit planes, which
|
||||
are very useful for drawing UI controls atop your 3D graphics. If the
|
||||
overlay hardware is not provided, FLTK tries to simulate the overlay,
|
||||
This works pretty well if your graphics are double buffered, but not
|
||||
very well for single-buffered. </P>
|
||||
<H3>Methods</H3>
|
||||
<CENTER>
|
||||
<TABLE width=90%>
|
||||
<TR><TD align=left valign=top>
|
||||
<UL>
|
||||
<LI><A href=#Fl_Gl_Window.Fl_Gl_Window>Fl_Gl_Window</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.~Fl_Gl_Window>~Fl_Gl_Window</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.can_do>can_do</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.can_do_overlay>can_do_overlay</A></LI>
|
||||
</UL>
|
||||
</TD><TD align=left valign=top>
|
||||
<UL>
|
||||
<LI><A href=#Fl_Gl_Window.draw>draw</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.draw_overlay>draw_overlay</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.handle>handle</A></LI>
|
||||
</UL>
|
||||
</TD><TD align=left valign=top>
|
||||
<UL>
|
||||
<LI><A href=#Fl_Gl_Window.hide>hide</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.invalidate>invalidate</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.make_current>make_current</A></LI>
|
||||
</UL>
|
||||
</TD><TD align=left valign=top>
|
||||
<UL>
|
||||
<LI><A href=#Fl_Gl_Window.make_overlay_current>make_overlay_current</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.mode>mode</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.ortho>ortho</A></LI>
|
||||
</UL>
|
||||
</TD><TD align=left valign=top>
|
||||
<UL>
|
||||
<LI><A href=#Fl_Gl_Window.redraw_overlay>redraw_overlay</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.swap_buffers>swap_buffers</A></LI>
|
||||
<LI><A href=#Fl_Gl_Window.valid>valid</A></LI>
|
||||
</UL>
|
||||
</TD></TR>
|
||||
</TABLE>
|
||||
</CENTER>
|
||||
<H4><A name=Fl_Gl_Window.Fl_Gl_Window>Fl_Gl_Window::Fl_Gl_Window(int x,
|
||||
int y, int w, int h, const char *label = 0)</A></H4>
|
||||
Creates a new <TT>Fl_Gl_Window</TT> widget using the given position,
|
||||
size, and label string. The default boxtype is <TT>FL_NO_BOX</TT>. The
|
||||
default mode is <TT>FL_RGB|FL_DOUBLE|FL_DEPTH</TT>.
|
||||
<H4><A name=Fl_Gl_Window.~Fl_Gl_Window>virtual
|
||||
Fl_Gl_Window::~Fl_Gl_Window()</A></H4>
|
||||
The destructor removes the widget and destroys the OpenGL context
|
||||
associated with it.
|
||||
<H4><A name=Fl_Gl_Window.draw>virtual void Fl_Gl_Window::draw(void)</A></H4>
|
||||
<TT>Fl_Gl_Window::draw()</TT> is a pure virtual method. You must
|
||||
subclass <TT>Fl_Gl_Window</TT> and provide an implementation for <TT>
|
||||
draw()</TT>. You may also provide an implementation of draw_overlay()
|
||||
if you want to draw into the overlay planes. You can avoid
|
||||
reinitializing the viewport and lights and other things by checking <TT>
|
||||
valid()</TT> at the start of <TT>draw()</TT> and only doing the
|
||||
initialization if it is false.
|
||||
<P>The <TT>draw()</TT> method can <I>only</I> use OpenGL calls. Do not
|
||||
attempt to call X, any of the functions in <FL/fl_draw.H>, or <TT>glX</TT>
|
||||
directly. Do not call <TT>gl_start()</TT> or <TT>gl_finish()</TT>. </P>
|
||||
<P>If double-buffering is enabled in the window, the back and front
|
||||
buffers are swapped after this function is completed. </P>
|
||||
<H4><A name=Fl_Gl_Window.mode>const int Fl_Gl_Window::mode() const
|
||||
<BR> int Fl_Gl_Window::mode(int m)</A></H4>
|
||||
Set or change the OpenGL capabilites of the window. The value can be
|
||||
any of the following OR'd together:
|
||||
<UL>
|
||||
<LI><TT>FL_RGB</TT> - RGB color (not indexed) </LI>
|
||||
<LI><TT>FL_RGB8</TT> - RGB color with at least 8 bits of each color </LI>
|
||||
<LI><TT>FL_INDEX</TT> - Indexed mode </LI>
|
||||
<LI><TT>FL_SINGLE</TT> - not double buffered </LI>
|
||||
<LI><TT>FL_DOUBLE</TT> - double buffered </LI>
|
||||
<LI><TT>FL_ACCUM</TT> - accumulation buffer </LI>
|
||||
<LI><TT>FL_ALPHA</TT> - alpha channel in color </LI>
|
||||
<LI><TT>FL_DEPTH</TT> - depth buffer </LI>
|
||||
<LI><TT>FL_STENCIL</TT> - stencil buffer </LI>
|
||||
<LI><TT>FL_MULTISAMPLE</TT> - multisample antialiasing </LI>
|
||||
</UL>
|
||||
<TT>FL_RGB</TT> and <TT>FL_SINGLE</TT> have a value of zero, so they
|
||||
are "on" unless you give <TT>FL_INDEX</TT> or <TT>FL_DOUBLE</TT>.
|
||||
<P>If the desired combination cannot be done, FLTK will try turning off <TT>
|
||||
FL_MULTISAMPLE</TT>. If this also fails the <TT>show()</TT> will call <TT>
|
||||
Fl::error()</TT> and not show the window. </P>
|
||||
<P>You can change the mode while the window is displayed. This is most
|
||||
useful for turning double-buffering on and off. Under X this will
|
||||
cause the old X window to be destroyed and a new one to be created. If
|
||||
this is a top-level window this will unfortunately also cause the
|
||||
window to blink, raise to the top, and be de-iconized, and the <TT>xid()</TT>
|
||||
will change, possibly breaking other code. It is best to make the GL
|
||||
window a child of another window if you wish to do this! </P>
|
||||
<H4><A name=Fl_Gl_Window.can_do>static int Fl_Gl_Window::can_do(int)
|
||||
<BR> int Fl_Gl_Window::can_do() const</A></H4>
|
||||
Returns non-zero if the hardware supports the given or current OpenGL
|
||||
mode.
|
||||
<H4><A name=Fl_Gl_Window.valid>char Fl_Gl_Window::valid() const
|
||||
<BR> void Fl_Gl_Window::valid(char i)</A></H4>
|
||||
<TT>Fl_Gl_Window::valid()</TT> is turned off when FLTK creates a new
|
||||
context for this window or when the window resizes, and is turned on <I>
|
||||
after</I><TT>draw()</TT> is called. You can use this inside your <TT>
|
||||
draw()</TT> method to avoid unneccessarily initializing the OpenGL
|
||||
context. Just do this:
|
||||
<UL>
|
||||
<PRE>
|
||||
void mywindow::draw() {
|
||||
if (!valid()) {
|
||||
glViewport(0,0,w(),h());
|
||||
@@ -171,16 +139,17 @@ void mywindow::draw() {
|
||||
... draw your geometry here ...
|
||||
}
|
||||
|
||||
<br>void Fl_Gl_Window::invalidate();
|
||||
<br>void Fl_Gl_Window::valid(char i);</a></h4>
|
||||
<BR>void Fl_Gl_Window::invalidate();
|
||||
<BR>void Fl_Gl_Window::valid(char i);
|
||||
|
||||
<tt>Fl_Gl_Window::valid()</tt> is turned off when FLTK creates a
|
||||
<TT>Fl_Gl_Window::valid()</TT> is turned off when FLTK creates a
|
||||
new context for this window and by the window resizing, and is turned
|
||||
on <i>after</i> draw() is called. You can use this inside your draw()
|
||||
on <I>after</I> draw() is called. You can use this inside your draw()
|
||||
method to avoid unneccessarily initializing the OpenGL context. Just
|
||||
do this:
|
||||
|
||||
<pre><tt>void mywindow::draw() {
|
||||
</PRE>
|
||||
<PRE><TT>void mywindow::draw() {
|
||||
if (!valid()) {
|
||||
glViewport(0,0,w(),h());
|
||||
glFrustum(...);
|
||||
@@ -189,77 +158,61 @@ do this:
|
||||
}
|
||||
... draw your geometry here ...
|
||||
}
|
||||
</pre></ul>
|
||||
|
||||
You can turn <tt>valid()</tt> on by calling <tt>valid(1)</tt>. You
|
||||
should only do this after fixing the transformation inside a
|
||||
<tt>draw()</tt> or after <tt>make_current()</tt>. This is done
|
||||
automatically after <tt>draw()</tt> returns.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.invalidate">void Fl_Gl_Window::invalidate()</a></h4>
|
||||
|
||||
The <tt>invalidate()</tt> method turns off <tt>valid()</tt> and is
|
||||
equivalent to calling <tt>value(0)</tt>.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.ortho">void Fl_Gl_Window::ortho()</a></h4>
|
||||
|
||||
Set the projection so 0,0 is in the lower left of the window and each
|
||||
pixel is 1 unit wide/tall. If you are drawing 2D images, your
|
||||
<tt>draw()</tt> method may want to call this if <tt>valid()</tt> is
|
||||
false.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.make_current">void Fl_Gl_Window::make_current()</a></h4>
|
||||
|
||||
The <tt>make_current()</tt> method selects the OpenGL context for the
|
||||
widget. It is called automatically prior to the <tt>draw()</tt> method
|
||||
being called and can also be used to implement feedback and/or selection
|
||||
within the <tt>handle()</tt> method.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.make_overlay_current">void Fl_Gl_Window::make_overlay_current()</a></h4>
|
||||
|
||||
The <tt>make_overlay_current()</tt> method selects the OpenGL context
|
||||
for the widget's overlay. It is called automatically prior to the
|
||||
<tt>draw_overlay()</tt> method being called and can also be used to
|
||||
implement feedback and/or selection within the <tt>handle()</tt>
|
||||
method.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.swap_buffers">void Fl_Gl_Window::swap_buffers()</a></h4>
|
||||
|
||||
The <tt>swap_buffers()</tt> method swaps the back and front buffers.
|
||||
It is called automatically after the <tt>draw()</tt> method is called.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.hide">void Fl_Gl_Window::hide()</a></h4>
|
||||
|
||||
Hides the window and destroys the OpenGL context.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.can_do_overlay">int Fl_Gl_Window::can_do_overlay()</a></h4>
|
||||
|
||||
Returns true if the hardware overlay is possible. If this is false,
|
||||
FLTK will try to simulate the overlay, with significant loss of update
|
||||
speed. Calling this will cause FLTK to open the display.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.redraw_overlay">void Fl_Gl_Window::redraw_overlay()</a></h4>
|
||||
|
||||
This method causes <tt>draw_overlay</tt> to be called at a later time.
|
||||
Initially the overlay is clear, if you want the window to display
|
||||
something in the overlay when it first appears, you must call this
|
||||
immediately after you <tt>show()</tt> your window.
|
||||
|
||||
<h4><a name="Fl_Gl_Window.draw_overlay">virtual void Fl_Gl_Window::draw_overlay()</a></h4>
|
||||
|
||||
You must implement this virtual function if you want to draw into the
|
||||
overlay. The overlay is cleared before this is called. You should
|
||||
draw anything that is not clear using OpenGL. You must use
|
||||
<tt>gl_color(i)</tt> to choose colors (it allocates them from the colormap
|
||||
using system-specific calls), and remember that you are in an indexed
|
||||
OpenGL mode and drawing anything other than flat-shaded will probably
|
||||
not work.
|
||||
|
||||
<p>Both this function and <tt>Fl_Gl_Window::draw()</tt> should check
|
||||
<tt>Fl_Gl_Window::valid()</tt> and set the same transformation. If you
|
||||
don't your code may not work on other systems. Depending on the OS,
|
||||
and on whether overlays are real or simulated, the OpenGL context may
|
||||
be the same or different between the overlay and main window.
|
||||
|
||||
</body>
|
||||
</html>
|
||||
</TT></PRE>
|
||||
</UL>
|
||||
You can turn <TT>valid()</TT> on by calling <TT>valid(1)</TT>. You
|
||||
should only do this after fixing the transformation inside a <TT>draw()</TT>
|
||||
or after <TT>make_current()</TT>. This is done automatically after <TT>
|
||||
draw()</TT> returns.
|
||||
<H4><A name=Fl_Gl_Window.invalidate>void Fl_Gl_Window::invalidate()</A></H4>
|
||||
The <TT>invalidate()</TT> method turns off <TT>valid()</TT> and is
|
||||
equivalent to calling <TT>value(0)</TT>.
|
||||
<H4><A name=Fl_Gl_Window.ortho>void Fl_Gl_Window::ortho()</A></H4>
|
||||
Set the projection so 0,0 is in the lower left of the window and each
|
||||
pixel is 1 unit wide/tall. If you are drawing 2D images, your <TT>
|
||||
draw()</TT> method may want to call this if <TT>valid()</TT> is false.
|
||||
<H4><A name=Fl_Gl_Window.make_current>void Fl_Gl_Window::make_current()</A>
|
||||
</H4>
|
||||
The <TT>make_current()</TT> method selects the OpenGL context for the
|
||||
widget. It is called automatically prior to the <TT>draw()</TT> method
|
||||
being called and can also be used to implement feedback and/or
|
||||
selection within the <TT>handle()</TT> method.
|
||||
<H4><A name=Fl_Gl_Window.make_overlay_current>void
|
||||
Fl_Gl_Window::make_overlay_current()</A></H4>
|
||||
The <TT>make_overlay_current()</TT> method selects the OpenGL context
|
||||
for the widget's overlay. It is called automatically prior to the <TT>
|
||||
draw_overlay()</TT> method being called and can also be used to
|
||||
implement feedback and/or selection within the <TT>handle()</TT>
|
||||
method.
|
||||
<H4><A name=Fl_Gl_Window.swap_buffers>void Fl_Gl_Window::swap_buffers()</A>
|
||||
</H4>
|
||||
The <TT>swap_buffers()</TT> method swaps the back and front buffers.
|
||||
It is called automatically after the <TT>draw()</TT> method is called.
|
||||
<H4><A name=Fl_Gl_Window.hide>void Fl_Gl_Window::hide()</A></H4>
|
||||
Hides the window and destroys the OpenGL context.
|
||||
<H4><A name=Fl_Gl_Window.can_do_overlay>int
|
||||
Fl_Gl_Window::can_do_overlay()</A></H4>
|
||||
Returns true if the hardware overlay is possible. If this is false,
|
||||
FLTK will try to simulate the overlay, with significant loss of update
|
||||
speed. Calling this will cause FLTK to open the display.
|
||||
<H4><A name=Fl_Gl_Window.redraw_overlay>void
|
||||
Fl_Gl_Window::redraw_overlay()</A></H4>
|
||||
This method causes <TT>draw_overlay</TT> to be called at a later time.
|
||||
Initially the overlay is clear, if you want the window to display
|
||||
something in the overlay when it first appears, you must call this
|
||||
immediately after you <TT>show()</TT> your window.
|
||||
<H4><A name=Fl_Gl_Window.draw_overlay>virtual void
|
||||
Fl_Gl_Window::draw_overlay()</A></H4>
|
||||
You must implement this virtual function if you want to draw into the
|
||||
overlay. The overlay is cleared before this is called. You should
|
||||
draw anything that is not clear using OpenGL. You must use <TT>
|
||||
gl_color(i)</TT> to choose colors (it allocates them from the colormap
|
||||
using system-specific calls), and remember that you are in an indexed
|
||||
OpenGL mode and drawing anything other than flat-shaded will probably
|
||||
not work.
|
||||
<P>Both this function and <TT>Fl_Gl_Window::draw()</TT> should check <TT>
|
||||
Fl_Gl_Window::valid()</TT> and set the same transformation. If you
|
||||
don't your code may not work on other systems. Depending on the OS,
|
||||
and on whether overlays are real or simulated, the OpenGL context may
|
||||
be the same or different between the overlay and main window. </P>
|
||||
</BODY></HTML>
|
||||
Reference in New Issue
Block a user