You may return to the Cvo Object Documenation Index from this document. This document contains the following sections describing the Cvo_Paint object:
Cvo_Paint
Cvo_Window
#include
<Cvo/Paint.h++>
new
Cvo_Paint ( char *resource_name,
{ Cvo_Object *parent | Display *display },
[ int width, int height ] )
The Cvo_Paint object provides a canvas on which the application may draw. If width and height are provided, they specify how big the drawable area should be.
The Cvo_Paint object actually has two Cvo_Pixmap objects associated
with it. One is the currently displayed Cvo_Pixmap and the other is
the one in which the application draws, the drawable canvas. Calling
the Flush()
member function on the object will cause the
displayable Cvo_Pixmap to be updated with the contents of the
drawable Cvo_Pixmap.
This object defines the following member functions in addition to those defined by its parent and ancestor objects.
ResetCanvas (
int width,
int height,
[ BOOL copy ] )
This function resets the size of the canvas on which to draw. If the
copy argument is True
, or not provided, the new canvas will
not be erased. If copy is False
, the canvas will be erased.
Flush (
)
This function will update the canvas to display the drawable pixmap
and any changes which have been made since the last Flush()
.
MakeDirty (
)
This function informs the Cvo_Paint object that the drawable pixmap has changed. This only needs to be called if the application writes directly to the drawable pixmap.
Cvo_Pixmap *GetPixmap (
)
This function returns the drawable Cvo_Pixmap.
ConvertCoord (
int *x,
int *y )
This function converts the coordinates pointed to by x and y, which should be valid coordinates in the visible Cvo_Pixmap displayed by the Cvo_Paint object, to the equivalent coordinates in the drawable Cvo_Pixmap canvas.
Erase (
)
This function will erase the drawable and visible Cvo_Pixmap objects.
EraseArea (
int x,
int y,
int width,
int height )
This function erases the area whose origin is (x,y) and whose size is width x height pixels.
This function fills the entire canvas with color.
This function fills the area whose origin is (x,y) and whose size is width x height pixels with color.
SetWidth (
int width )
This function sets the width of lines drawn to be width.
This function draws a line from (x1,y1) to (x2,y2) using color.
This function draws a rectangle of size width x height starting at (x,y) in color.
This function uses the XDrawArc()
function to draw an arc in
color.
This functions draw a shape located at (x,y). If size is not passed the shape is about 6 pixels large, otherwise it is about size pixels large.
The shape argument must be one of the following:
CVOP_BOX_SHAPE
( An unfilled square)
CVOP_CIRCLE_SHAPE
( An unfilled circle)
CVOP_DISC_SHAPE
( A filled circle)
CVOP_POINT_SHAPE
( A single pixel)
CVOP_SQUARE_SHAPE
( A filled square)
CVOP_X_SHAPE
( An X)
PanTo (
int x,
int y )
Pan the visible image such that (x,y) in the image is located in the upper right hand corner of the Cvo_Paint object. Cvo will silently modify the x and y value if they are out of range for the image.
int PWidth (
)
int PHeight (
)
Return the width or height of the the image, not of the Cvo_Paint object itself.
This object modifies the following X resources which are used by its parent or other ancestors.
*CvoPaint.Sunken
(new value:
True
)
See the example source code for an example of how to use this object.
See the legend for information about the conventions used in this documentation.