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><H1
><A
NAME="GNOMECANVAS"
>GnomeCanvas</A
></H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN10062"
></A
><H2
>Name</H2
>GnomeCanvas -- A generic engine for structured graphics.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN10065"
></A
><H2
>Synopsis</H2
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="SYNOPSIS"
> #include <gnome.h>
struct <A
HREF="gnomecanvas.html#GNOMECANVAS-STRUCT"
>GnomeCanvas</A
>;
#define <A
HREF="gnomecanvas.html#GNOME-CANVAS-EPSILON-CAPS"
>GNOME_CANVAS_EPSILON</A
>
#define <A
HREF="gnomecanvas.html#GNOME-CANVAS-COLOR-CAPS"
>GNOME_CANVAS_COLOR</A
> (r, g, b)
#define <A
HREF="gnomecanvas.html#GNOME-CANVAS-COLOR-A-CAPS"
>GNOME_CANVAS_COLOR_A</A
> (r, g, b, a)
struct <A
HREF="gnomecanvas.html#GNOMECANVASBUF"
>GnomeCanvasBuf</A
>;
<GTKDOCLINK
HREF="GTKWIDGET"
>GtkWidget</GTKDOCLINK
>* <A
HREF="gnomecanvas.html#GNOME-CANVAS-NEW"
>gnome_canvas_new</A
> (void);
<GTKDOCLINK
HREF="GTKWIDGET"
>GtkWidget</GTKDOCLINK
>* <A
HREF="gnomecanvas.html#GNOME-CANVAS-NEW-AA"
>gnome_canvas_new_aa</A
> (void);
<A
HREF="gnomecanvasgroup.html"
>GnomeCanvasGroup</A
>* <A
HREF="gnomecanvas.html#GNOME-CANVAS-ROOT"
>gnome_canvas_root</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-SET-SCROLL-REGION"
>gnome_canvas_set_scroll_region</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> x1,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> y1,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> x2,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> y2);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-GET-SCROLL-REGION"
>gnome_canvas_get_scroll_region</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *x1,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *y1,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *x2,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *y2);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-SET-PIXELS-PER-UNIT"
>gnome_canvas_set_pixels_per_unit</A
>
(<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> n);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-SCROLL-TO"
>gnome_canvas_scroll_to</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
int cx,
int cy);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-GET-SCROLL-OFFSETS"
>gnome_canvas_get_scroll_offsets</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
int *cx,
int *cy);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-UPDATE-NOW"
>gnome_canvas_update_now</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas);
<A
HREF="gnomecanvasitem.html"
>GnomeCanvasItem</A
>* <A
HREF="gnomecanvas.html#GNOME-CANVAS-GET-ITEM-AT"
>gnome_canvas_get_item_at</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> x,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> y);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-REQUEST-REDRAW-UTA"
>gnome_canvas_request_redraw_uta</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="ARTUTA"
>ArtUta</GTKDOCLINK
> *uta);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-REQUEST-REDRAW"
>gnome_canvas_request_redraw</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
int x1,
int y1,
int x2,
int y2);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-W2C-AFFINE"
>gnome_canvas_w2c_affine</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> affine[6]);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-W2C"
>gnome_canvas_w2c</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> wx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> wy,
int *cx,
int *cy);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-W2C-D"
>gnome_canvas_w2c_d</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> wx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> wy,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *cx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *cy);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-C2W"
>gnome_canvas_c2w</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
int cx,
int cy,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *wx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *wy);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-WINDOW-TO-WORLD"
>gnome_canvas_window_to_world</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> winx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> winy,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *worldx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *worldy);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-WORLD-TO-WINDOW"
>gnome_canvas_world_to_window</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> worldx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> worldy,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *winx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *winy);
int <A
HREF="gnomecanvas.html#GNOME-CANVAS-GET-COLOR"
>gnome_canvas_get_color</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
char *spec,
<GTKDOCLINK
HREF="GDKCOLOR"
>GdkColor</GTKDOCLINK
> *color);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-SET-STIPPLE-ORIGIN"
>gnome_canvas_set_stipple_origin</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="GDKGC"
>GdkGC</GTKDOCLINK
> *gc);
void <A
HREF="gnomecanvas.html#GNOME-CANVAS-SET-DITHER"
>gnome_canvas_set_dither</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="GDKRGBDITHER"
>GdkRgbDither</GTKDOCLINK
> dither);
<GTKDOCLINK
HREF="GDKRGBDITHER"
>GdkRgbDither</GTKDOCLINK
> <A
HREF="gnomecanvas.html#GNOME-CANVAS-GET-DITHER"
>gnome_canvas_get_dither</A
> (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas); </PRE
></TD
></TR
></TABLE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN10152"
></A
><H2
>Object Hierarchy</H2
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="SYNOPSIS"
> <GTKDOCLINK
HREF="GTKOBJECT"
>GtkObject</GTKDOCLINK
>
+----<GTKDOCLINK
HREF="GTKWIDGET"
>GtkWidget</GTKDOCLINK
>
+----<GTKDOCLINK
HREF="GTKCONTAINER"
>GtkContainer</GTKDOCLINK
>
+----<GTKDOCLINK
HREF="GTKLAYOUT"
>GtkLayout</GTKDOCLINK
>
+----GnomeCanvas</PRE
></TD
></TR
></TABLE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN10159"
></A
><H2
>Description</H2
><P
> The GNOME canvas is an engine for displaying structured graphics
and simplifying the development of complex graphic-based
applications.
</P
><DIV
CLASS="REFSECT2"
><A
NAME="AEN10162"
></A
><H3
>Canvas Items</H3
><P
> The GNOME Canvas basic building blocks are the GNOME Canvas
Items (<A
HREF="gnomecanvasitem.html"
>GnomeCanvasItem</A
>): lines, rectangles, text, ellipses,
polylines, images and embedded widgets. You can use any of
those directly in your application.
</P
><P
> The CanvasItem system is designed to be extensible.
Applications can define their own <A
HREF="gnomecanvasitem.html"
>GnomeCanvasItem</A
> objects for
special purpose tasks. For example, the GNOME Gnumeric
spreadsheet defines a number of special Canvas Items that are
specialized for the task of spreadsheets.
</P
><P
> Specialized canvas items allow the developer to write
custom items that can adapt to their needs for speed,
scalability and gives the user the power to extend the
canvas.
</P
><P
> Items on the canvas can be reconfigured by using the Gtk
argument system. Users can reconfigure the parameters of
the canvas items and the changes on the parameters will be
reflected immediately on the screen.
</P
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10170"
></A
><H3
>Flicker free display</H3
><P
> The GNOME Canvas uses off-screen buffers to render the images
before transferring them to the screen. Transfers can take
place at the command of the programmer (by explicitly
requesting a repaint update) or done automatically by the
engine (during the idle look handler).
</P
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10173"
></A
><H3
>Event dispatching</H3
><P
>Each
GnomeCanvasItem can receive mouse events, keyboard events,
mouse-enter and mouse leave events. In addition a canvas
item can grab the mouse (for example to implement reliable
dragging of objects).
</P
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10176"
></A
><H3
>Canvas types</H3
><P
> The Canvas can be run in two different modes: X11 mode and Art
mode. The mode is chosen at the creation time of the widget
by either calling <A
HREF="gnomecanvas.html#GNOME-CANVAS-NEW"
>gnome_canvas_new</A
>() or <A
HREF="gnomecanvas.html#GNOME-CANVAS-NEW-AA"
>gnome_canvas_new_aa</A
>(),
the former creates an X11 canvas, while the latter creates an
Art-based canvas.
</P
><P
> The X11 mode uses the X server to draw the items and it takes
advantage of the X server acceleration features for drawing on
the screen. The only drawback is that the output quality and
the imaging model are restricted to the X11 quality and
imaging model.
</P
><P
> The Art mode of the canvas has an advanced imaging model based
on LibArt and it allows any GnomeCanvasItem (with the
exception of the embedded widget item) to be rotated, scaled
and translated (this is done by means of applying an affine
transformation on the object).
</P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN10183"
></A
><H2
>Details</H2
><DIV
CLASS="REFSECT2"
><A
NAME="AEN10185"
></A
><H3
><A
NAME="GNOMECANVAS-STRUCT"
></A
>struct GnomeCanvas</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>struct GnomeCanvas;</PRE
></TD
></TR
></TABLE
><P
> Most of the fields in this structure are for private use only.
However, canvas item implementations may make use of some of them.
</P
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10190"
></A
><H3
><A
NAME="GNOME-CANVAS-EPSILON-CAPS"
></A
>GNOME_CANVAS_EPSILON</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>#define GNOME_CANVAS_EPSILON 1e-10</PRE
></TD
></TR
></TABLE
><P
> This macro defines a ‘small’ floating-point value for
the internal computations that the canvas performs. It can be
used by item implementations as a test to see whether a number is
“almost zero”.
</P
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10195"
></A
><H3
><A
NAME="GNOME-CANVAS-COLOR-CAPS"
></A
>GNOME_CANVAS_COLOR()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>#define GNOME_CANVAS_COLOR(r, g, b)</PRE
></TD
></TR
></TABLE
><P
> This macro is used to build a 32-bit integer with an RGB color
specification. The specified values must be integers in the range
[0, 255].
</P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10200"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>r</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
>Red component of the color.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>g</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
>Green component of the color.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>b</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
>Blue component of the color.
</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10217"
></A
><H3
><A
NAME="GNOME-CANVAS-COLOR-A-CAPS"
></A
>GNOME_CANVAS_COLOR_A()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>#define GNOME_CANVAS_COLOR_A(r, g, b, a)</PRE
></TD
></TR
></TABLE
><P
> This macro is used to build a 32-bit integer with an RGBA color
specification. This is the same as an RGB color specification,
but with an added alpha or opacity value. The specified values
must be integers in the range [0, 255].
</P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10222"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>r</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
>Red component of the color.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>g</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
>Green component of the color.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>b</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
>Blue component of the color.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>a</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
>Opacity component of the color.
</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10243"
></A
><H3
><A
NAME="GNOMECANVASBUF"
></A
>struct GnomeCanvasBuf</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>typedef struct {
/* 24-bit RGB buffer for rendering */
guchar *buf;
/* Rowstride for the buffer */
int buf_rowstride;
/* Rectangle describing the rendering area */
ArtIRect rect;
/* Background color, given as 0xrrggbb */
guint32 bg_color;
/* Invariant: at least one of the following flags is true. */
/* Set when the render rectangle area is the solid color bg_color */
unsigned int is_bg : 1;
/* Set when the render rectangle area is represented by the buf */
unsigned int is_buf : 1;
} GnomeCanvasBuf;</PRE
></TD
></TR
></TABLE
><P
> This structure is passed to the <TT
CLASS="FUNCTION"
>render</TT
> method
of canvas items when they need to paint themselves on an
antialiased canvas. The <TT
CLASS="STRUCTFIELD"
><I
>buf</I
></TT
> field
points to a 24-bit RGB buffer for rendering. The
<TT
CLASS="STRUCTFIELD"
><I
>buf_rowstride</I
></TT
> field specifies the
number of bytes in each row in the buffer, which should be used to
calculate byte offsets inside it. The buffer's pixel offsets in
canvas pixel coordinates are given by the
<TT
CLASS="STRUCTFIELD"
><I
>rect</I
></TT
> rectangle. The
<TT
CLASS="STRUCTFIELD"
><I
>is_bg</I
></TT
> and
<TT
CLASS="STRUCTFIELD"
><I
>is_buf</I
></TT
> fields are flags that items can
use to implement rendering optimizations, and they are used in
conjunction with the <TT
CLASS="STRUCTFIELD"
><I
>bg_color</I
></TT
> field.
</P
><P
> The <TT
CLASS="STRUCTFIELD"
><I
>is_buf</I
></TT
> flag specifies whether the
contents of the buffer are an accurate representation of the state
of the canvas. If this flag is true, then the RGB data in the
<TT
CLASS="STRUCTFIELD"
><I
>buf</I
></TT
> is valid, that is, it contains
meaningful data.
</P
><P
> The <TT
CLASS="STRUCTFIELD"
><I
>is_bg</I
></TT
> flag specifies whether the
buffer has all its pixels set to the same color. This allows
canvas items to optimize for this case by doing alpha compositing
for a smaller set of values than if the buffer had pixels of
different colors.
</P
><P
> At least one of these flags is on at any one time. The meaning of
their combinations is as follows:
<DIV
CLASS="TABLE"
><A
NAME="AEN10261"
></A
><P
><B
>Table 1. Values for <TT
CLASS="STRUCTFIELD"
><I
>is_bg</I
></TT
> and
<TT
CLASS="STRUCTFIELD"
><I
>is_buf</I
></TT
>
</B
></P
><TABLE
BORDER="1"
BGCOLOR="#FFFFFF"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><THEAD
><TR
><TH
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>is_buf</I
></TT
></TH
><TH
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>is_bg</I
></TT
></TH
><TH
ALIGN="LEFT"
VALIGN="TOP"
>Meaning</TH
></TR
></THEAD
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><SPAN
CLASS="SYMBOL"
>FALSE</SPAN
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><SPAN
CLASS="SYMBOL"
>TRUE</SPAN
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
> The buffer does not contain meaningful data. However,
it should be considered as if it were filled with the
solid color specified in the
<TT
CLASS="STRUCTFIELD"
><I
>bg_color</I
></TT
> field. Item
implementations may want to call
<TT
CLASS="FUNCTION"
><A
HREF="gnomeui-gnome-canvas-util.html#GNOME-CANVAS-BUF-ENSURE-BUF"
>gnome_canvas_buf_ensure_buf</A
>()</TT
> to
fill the buffer automatically.
</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><SPAN
CLASS="SYMBOL"
>TRUE</SPAN
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><SPAN
CLASS="SYMBOL"
>FALSE</SPAN
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
> The buffer contains meaningful data and not all of its
pixels may be the same color. Item implementations can
use the buffer data as-is for alpha compositing.
</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><SPAN
CLASS="SYMBOL"
>TRUE</SPAN
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><SPAN
CLASS="SYMBOL"
>TRUE</SPAN
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
> The buffer contains meaningful data, and all the pixels
are of the same color. Item implementations can use the
buffer data as-is for alpha compositing, or be smarter
and do less operations since they can just composite
over a single color.
</TD
></TR
></TBODY
></TABLE
></DIV
>
</P
><P
> Whenever an item paints to an RGB buffer in which the
<TT
CLASS="STRUCTFIELD"
><I
>is_bg</I
></TT
> field was true, the item is then
responsible for turning off this flag if it knows that the result
will not be pixels all of the same color. If a large item, like a
solid rectangle, knows that it will be filling the buffer with a
solid color, then it take any one of the following actions:
<P
></P
><UL
><LI
><P
> Fill the actual pixels in the buffer with the solid color
and turn off the <TT
CLASS="STRUCTFIELD"
><I
>is_bg</I
></TT
> flag. It
should then turn on the <TT
CLASS="STRUCTFIELD"
><I
>is_buf</I
></TT
>
flag.
</P
></LI
><LI
><P
> Fill the actual pixels in the buffer with the solid color,
set the <TT
CLASS="STRUCTFIELD"
><I
>bg_color</I
></TT
> field to that
same color, and turn on both the
<TT
CLASS="STRUCTFIELD"
><I
>is_bg</I
></TT
> and
<TT
CLASS="STRUCTFIELD"
><I
>is_buf</I
></TT
> flags. This is correct,
but is wasteful, since it could have done just the following
instead.
</P
></LI
><LI
><P
> Just set the <TT
CLASS="STRUCTFIELD"
><I
>bg_color</I
></TT
> to the
solid color, turn on the <TT
CLASS="STRUCTFIELD"
><I
>is_bg</I
></TT
>
flag, and turn off the <TT
CLASS="STRUCTFIELD"
><I
>is_buf</I
></TT
>
flag. This means that the buffer does not contain the
actual meaningful data, and the next item to be repainted
should look at the solid color instead. This is the most
efficient version.
</P
></LI
></UL
>
</P
><P
> Most item implementations may only need to perform the actions for
the first case described above. The other two are simply
optimizations they can perform.
</P
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10313"
></A
><H3
><A
NAME="GNOME-CANVAS-NEW"
></A
>gnome_canvas_new ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
><GTKDOCLINK
HREF="GTKWIDGET"
>GtkWidget</GTKDOCLINK
>* gnome_canvas_new (void);</PRE
></TD
></TR
></TABLE
><P
>Creates a new empty canvas in non-antialiased mode. If you wish to use the
&GnomeCanvasImage item inside this canvas, then you must push the gdk_imlib
visual and colormap before calling this function, and they can be popped
afterwards.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10320"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Returns</I
></SPAN
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A newly-created canvas.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10329"
></A
><H3
><A
NAME="GNOME-CANVAS-NEW-AA"
></A
>gnome_canvas_new_aa ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
><GTKDOCLINK
HREF="GTKWIDGET"
>GtkWidget</GTKDOCLINK
>* gnome_canvas_new_aa (void);</PRE
></TD
></TR
></TABLE
><P
>Creates a new empty canvas in antialiased mode. You should push the GdkRGB
visual and colormap before calling this functions, and they can be popped
afterwards.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10336"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Returns</I
></SPAN
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A newly-created antialiased canvas.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10345"
></A
><H3
><A
NAME="GNOME-CANVAS-ROOT"
></A
>gnome_canvas_root ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
><A
HREF="gnomecanvasgroup.html"
>GnomeCanvasGroup</A
>* gnome_canvas_root (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas);</PRE
></TD
></TR
></TABLE
><P
>Queries the root group of a canvas.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10353"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Returns</I
></SPAN
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> The root group of the specified canvas.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10366"
></A
><H3
><A
NAME="GNOME-CANVAS-SET-SCROLL-REGION"
></A
>gnome_canvas_set_scroll_region ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_set_scroll_region (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> x1,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> y1,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> x2,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> y2);</PRE
></TD
></TR
></TABLE
><P
>Sets the scrolling region of a canvas to the specified rectangle. The canvas
will then be able to scroll only within this region. The view of the canvas
is adjusted as appropriate to display as much of the new region as possible.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10377"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>x1</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Leftmost limit of the scrolling region.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>y1</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Upper limit of the scrolling region.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>x2</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Rightmost limit of the scrolling region.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>y2</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Lower limit of the scrolling region.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10402"
></A
><H3
><A
NAME="GNOME-CANVAS-GET-SCROLL-REGION"
></A
>gnome_canvas_get_scroll_region ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_get_scroll_region (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *x1,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *y1,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *x2,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *y2);</PRE
></TD
></TR
></TABLE
><P
>Queries the scrolling region of a canvas.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10413"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>x1</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Leftmost limit of the scrolling region (return value).</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>y1</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Upper limit of the scrolling region (return value).</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>x2</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Rightmost limit of the scrolling region (return value).</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>y2</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Lower limit of the scrolling region (return value).</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10438"
></A
><H3
><A
NAME="GNOME-CANVAS-SET-PIXELS-PER-UNIT"
></A
>gnome_canvas_set_pixels_per_unit ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_set_pixels_per_unit
(<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> n);</PRE
></TD
></TR
></TABLE
><P
>Sets the zooming factor of a canvas by specifying the number of pixels that
correspond to one canvas unit.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10446"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>n</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> The number of pixels that correspond to one canvas unit.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10459"
></A
><H3
><A
NAME="GNOME-CANVAS-SCROLL-TO"
></A
>gnome_canvas_scroll_to ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_scroll_to (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
int cx,
int cy);</PRE
></TD
></TR
></TABLE
><P
>Makes a canvas scroll to the specified offsets, given in canvas pixel units.
The canvas will adjust the view so that it is not outside the scrolling
region. This function is typically not used, as it is better to hook
scrollbars to the canvas layout's scrolling adjusments.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10466"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Horizontal scrolling offset in canvas pixel units.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Vertical scrolling offset in canvas pixel units.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10483"
></A
><H3
><A
NAME="GNOME-CANVAS-GET-SCROLL-OFFSETS"
></A
>gnome_canvas_get_scroll_offsets ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_get_scroll_offsets (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
int *cx,
int *cy);</PRE
></TD
></TR
></TABLE
><P
>Queries the scrolling offsets of a canvas. The values are returned in canvas
pixel units.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10490"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Horizontal scrolling offset (return value).</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Vertical scrolling offset (return value).</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10507"
></A
><H3
><A
NAME="GNOME-CANVAS-UPDATE-NOW"
></A
>gnome_canvas_update_now ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_update_now (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas);</PRE
></TD
></TR
></TABLE
><P
>Forces an immediate update and redraw of a canvas. If the canvas does not
have any pending update or redraw requests, then no action is taken. This is
typically only used by applications that need explicit control of when the
display is updated, like games. It is not needed by normal applications.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10514"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10523"
></A
><H3
><A
NAME="GNOME-CANVAS-GET-ITEM-AT"
></A
>gnome_canvas_get_item_at ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
><A
HREF="gnomecanvasitem.html"
>GnomeCanvasItem</A
>* gnome_canvas_get_item_at (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> x,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> y);</PRE
></TD
></TR
></TABLE
><P
>Looks for the item that is under the specified position, which must be
specified in world coordinates.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10533"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>x</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> X position in world coordinates.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>y</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Y position in world coordinates.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Returns</I
></SPAN
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> The sought item, or NULL if no item is at the specified
coordinates.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10554"
></A
><H3
><A
NAME="GNOME-CANVAS-REQUEST-REDRAW-UTA"
></A
>gnome_canvas_request_redraw_uta ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_request_redraw_uta (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="ARTUTA"
>ArtUta</GTKDOCLINK
> *uta);</PRE
></TD
></TR
></TABLE
><P
>Informs a canvas that the specified area, given as a microtile array, needs
to be repainted. To be used only by item implementations.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10562"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>uta</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Microtile array that specifies the area to be redrawn.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10575"
></A
><H3
><A
NAME="GNOME-CANVAS-REQUEST-REDRAW"
></A
>gnome_canvas_request_redraw ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_request_redraw (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
int x1,
int y1,
int x2,
int y2);</PRE
></TD
></TR
></TABLE
><P
>Convenience function that informs a canvas that the specified rectangle needs
to be repainted. This function converts the rectangle to a microtile array
and feeds it to <A
HREF="gnomecanvas.html#GNOME-CANVAS-REQUEST-REDRAW-UTA"
>gnome_canvas_request_redraw_uta</A
>(). The rectangle includes
<TT
CLASS="PARAMETER"
><I
>x1</I
></TT
> and <TT
CLASS="PARAMETER"
><I
>y1</I
></TT
>, but not <TT
CLASS="PARAMETER"
><I
>x2</I
></TT
> and <TT
CLASS="PARAMETER"
><I
>y2</I
></TT
>. To be used only by item implementations.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10587"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>x1</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Leftmost coordinate of the rectangle to be redrawn.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>y1</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Upper coordinate of the rectangle to be redrawn.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>x2</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Rightmost coordinate of the rectangle to be redrawn, plus 1.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>y2</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Lower coordinate of the rectangle to be redrawn, plus 1.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10612"
></A
><H3
><A
NAME="GNOME-CANVAS-W2C-AFFINE"
></A
>gnome_canvas_w2c_affine ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_w2c_affine (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> affine[6]);</PRE
></TD
></TR
></TABLE
><P
>Gets the affine transform that converts from world coordinates to canvas
pixel coordinates.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10620"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>affine</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> An affine transformation matrix (return value).</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10633"
></A
><H3
><A
NAME="GNOME-CANVAS-W2C"
></A
>gnome_canvas_w2c ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_w2c (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> wx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> wy,
int *cx,
int *cy);</PRE
></TD
></TR
></TABLE
><P
>Converts world coordinates into canvas pixel coordinates.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10642"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>wx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> World X coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>wy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> World Y coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> X pixel coordinate (return value).</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Y pixel coordinate (return value).</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10667"
></A
><H3
><A
NAME="GNOME-CANVAS-W2C-D"
></A
>gnome_canvas_w2c_d ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_w2c_d (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> wx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> wy,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *cx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *cy);</PRE
></TD
></TR
></TABLE
><P
>Converts world coordinates into canvas pixel coordinates. This version</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10678"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>wx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> World X coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>wy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> World Y coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> X pixel coordinate (return value).</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Y pixel coordinate (return value).</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10703"
></A
><H3
><A
NAME="GNOME-CANVAS-C2W"
></A
>gnome_canvas_c2w ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_c2w (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
int cx,
int cy,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *wx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *wy);</PRE
></TD
></TR
></TABLE
><P
>Converts canvas pixel coordinates to world coordinates.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10712"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Canvas pixel X coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>cy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Canvas pixel Y coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>wx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> X world coordinate (return value).</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>wy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Y world coordinate (return value).</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10737"
></A
><H3
><A
NAME="GNOME-CANVAS-WINDOW-TO-WORLD"
></A
>gnome_canvas_window_to_world ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_window_to_world (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> winx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> winy,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *worldx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *worldy);</PRE
></TD
></TR
></TABLE
><P
>Converts window-relative coordinates into world coordinates. You can use
this when you need to convert mouse coordinates into world coordinates, for
example.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10748"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>winx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Window-relative X coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>winy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Window-relative Y coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>worldx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> X world coordinate (return value).</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>worldy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Y world coordinate (return value).</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10773"
></A
><H3
><A
NAME="GNOME-CANVAS-WORLD-TO-WINDOW"
></A
>gnome_canvas_world_to_window ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_world_to_window (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> worldx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> worldy,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *winx,
<GTKDOCLINK
HREF="DOUBLE"
>double</GTKDOCLINK
> *winy);</PRE
></TD
></TR
></TABLE
><P
>Converts world coordinates into window-relative coordinates.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10784"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>worldx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> World X coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>worldy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> World Y coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>winx</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> X window-relative coordinate.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>winy</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Y window-relative coordinate.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10809"
></A
><H3
><A
NAME="GNOME-CANVAS-GET-COLOR"
></A
>gnome_canvas_get_color ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>int gnome_canvas_get_color (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
char *spec,
<GTKDOCLINK
HREF="GDKCOLOR"
>GdkColor</GTKDOCLINK
> *color);</PRE
></TD
></TR
></TABLE
><P
>Allocates a color based on the specified X color specification. As a
convenience to item implementations, it returns TRUE if the color was
allocated, or FALSE if the specification was NULL. A NULL color
specification is considered as "transparent" by the canvas.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10817"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>spec</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> X color specification, or NULL for "transparent".</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>color</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Returns the allocated color.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Returns</I
></SPAN
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> TRUE if <TT
CLASS="PARAMETER"
><I
>spec</I
></TT
> is non-NULL and the color is allocated. If <TT
CLASS="PARAMETER"
><I
>spec</I
></TT
>
is NULL, then returns FALSE.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10840"
></A
><H3
><A
NAME="GNOME-CANVAS-SET-STIPPLE-ORIGIN"
></A
>gnome_canvas_set_stipple_origin ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_set_stipple_origin (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="GDKGC"
>GdkGC</GTKDOCLINK
> *gc);</PRE
></TD
></TR
></TABLE
><P
>Sets the stipple origin of the specified GC as is appropriate for the canvas,
so that it will be aligned with other stipple patterns used by canvas items.
This is typically only needed by item implementations.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10848"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>gc</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> GC on which to set the stipple origin.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10861"
></A
><H3
><A
NAME="GNOME-CANVAS-SET-DITHER"
></A
>gnome_canvas_set_dither ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
>void gnome_canvas_set_dither (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas,
<GTKDOCLINK
HREF="GDKRGBDITHER"
>GdkRgbDither</GTKDOCLINK
> dither);</PRE
></TD
></TR
></TABLE
><P
>Controls dithered rendering for antialiased canvases. The value of dither
should be; <GTKDOCLINK
HREF="GDK-RGB-DITHER-NONE-CAPS"
>GDK_RGB_DITHER_NONE</GTKDOCLINK
>, <GTKDOCLINK
HREF="GDK-RGB-DITHER-NORMAL-CAPS"
>GDK_RGB_DITHER_NORMAL</GTKDOCLINK
>, or
<GTKDOCLINK
HREF="GDK-RGB-DITHER-MAX-CAPS"
>GDK_RGB_DITHER_MAX</GTKDOCLINK
>. The default canvas setting is <GTKDOCLINK
HREF="GDK-RGB-DITHER-NORMAL-CAPS"
>GDK_RGB_DITHER_NORMAL</GTKDOCLINK
>.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10873"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>dither</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> Type of dither used to render an antialiased canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Returns</I
></SPAN
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> </TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><HR><DIV
CLASS="REFSECT2"
><A
NAME="AEN10890"
></A
><H3
><A
NAME="GNOME-CANVAS-GET-DITHER"
></A
>gnome_canvas_get_dither ()</H3
><TABLE
BORDER="0"
BGCOLOR="#D6E8FF"
WIDTH="100%"
CELLPADDING="6"
><TR
><TD
><PRE
CLASS="PROGRAMLISTING"
><GTKDOCLINK
HREF="GDKRGBDITHER"
>GdkRgbDither</GTKDOCLINK
> gnome_canvas_get_dither (<A
HREF="gnomecanvas.html"
>GnomeCanvas</A
> *canvas);</PRE
></TD
></TR
></TABLE
><P
>Returns the type of dithering used to render an antialiased canvas.</P
><P
></P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN10898"
></A
><P
></P
><TABLE
BORDER="0"
WIDTH="100%"
BGCOLOR="#FFD0D0"
CELLSPACING="0"
CELLPADDING="4"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><TT
CLASS="PARAMETER"
><I
>canvas</I
></TT
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> A canvas.</TD
></TR
><TR
><TD
WIDTH="20%"
ALIGN="RIGHT"
VALIGN="TOP"
><SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Returns</I
></SPAN
> :</TD
><TD
WIDTH="80%"
ALIGN="LEFT"
VALIGN="TOP"
> The dither setting.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN10911"
></A
><H2
>See Also</H2
><P
> <A
HREF="gnomecanvasitem.html"
>GnomeCanvasItem</A
>, <A
HREF="gnomecanvasgroup.html"
>GnomeCanvasGroup</A
>, GnomeCanvasRE,
<GTKDOCLINK
HREF="GNOMECANVASRECTELLIPSE"
>GnomeCanvasRectEllipse</GTKDOCLINK
>, <A
HREF="gnomecanvasimage.html"
>GnomeCanvasImage</A
>, <A
HREF="gnomecanvasline.html"
>GnomeCanvasLine</A
>,
<A
HREF="gnomecanvaspolygon.html"
>GnomeCanvasPolygon</A
>, <A
HREF="gnomecanvastext.html"
>GnomeCanvasText</A
>, <A
HREF="gnomecanvaswidget.html"
>GnomeCanvasWidget</A
>
</P
></DIV
><DIV
CLASS="NAVFOOTER"
><BR
CLEAR="all"><BR><TABLE
WIDTH="100%"
BORDER="0"
BGCOLOR="#000000"
CELLPADDING="1"
CELLSPACING="0"
><TR
><TD
WIDTH="25%"
BGCOLOR="#C00000"
ALIGN="left"
><A
HREF="gnomecalculator.html"
><FONT
COLOR="#FFFFFF"
SIZE="3"
><B
><<< Previous Page</B
></FONT
></A
></TD
><TD
WIDTH="25%"
BGCOLOR="#0000C0"
ALIGN="center"
><FONT
COLOR="#FFFFFF"
SIZE="3"
><B
><A
HREF="book1.html"
><FONT
COLOR="#FFFFFF"
SIZE="3"
><B
>Home</B
></FONT
></A
></B
></FONT
></TD
><TD
WIDTH="25%"
BGCOLOR="#00C000"
ALIGN="center"
><FONT
COLOR="#FFFFFF"
SIZE="3"
><B
><A
HREF="gnome-objects.html"
><FONT
COLOR="#FFFFFF"
SIZE="3"
><B
>Up</B
></FONT
></A
></B
></FONT
></TD
><TD
WIDTH="25%"
BGCOLOR="#C00000"
ALIGN="right"
><A
HREF="gnomecanvasitem.html"
><FONT
COLOR="#FFFFFF"
SIZE="3"
><B
>Next Page >>></B
></FONT
></A
></TD
></TR
><TR
><TD
COLSPAN="2"
ALIGN="left"
><FONT
COLOR="#FFFFFF"
SIZE="3"
><B
>GnomeCalculator</B
></FONT
></TD
><TD
COLSPAN="2"
ALIGN="right"
><FONT
COLOR="#FFFFFF"
SIZE="3"
><B
>GnomeCanvasItem</B
></FONT
></TD
></TR
></TABLE
></DIV
></BODY
></HTML
>
distrib
>
Mandriva
>
2010.0
>
i586
>
media
>
contrib-release
>
by-pkgid
>
1bbf51ece72e40a5f40ad48678e7c5a5
>
files
>
430
