Tk_CanvasPs(3)						       Tk Library Procedures						    Tk_CanvasPs(3)

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NAME

       Tk_CanvasPsY, Tk_CanvasPsBitmap, Tk_CanvasPsColor, Tk_CanvasPsFont, Tk_CanvasPsPath, Tk_CanvasPsStipple - utility procedures for generating
       Postscript for canvases

SYNOPSIS

       #include <tk.h>

       double
       Tk_CanvasPsY(canvas, canvasY)

       int
       Tk_CanvasPsBitmap(interp, canvas, bitmap, x, y, width, height)

       int
       Tk_CanvasPsColor(interp, canvas, colorPtr)

       int
       Tk_CanvasPsFont(interp, canvas, tkFont)

       Tk_CanvasPsPath(interp, canvas, coordPtr, numPoints)

       int
       Tk_CanvasPsStipple(interp, canvas, bitmap)

ARGUMENTS

       Tk_Canvas canvas (in)		    A token that identifies a canvas widget for which Postscript is being generated.

       double canvasY (in)		    Y-coordinate in the space of the canvas.

       Tcl_Interp *interp (in/out)	    A Tcl interpreter;	Postscript is appended to its result, or the result may be replaced with an  error
					    message.

       Pixmap bitmap (in)		    Bitmap to use for generating Postscript.

       int x (in)			    X-coordinate within bitmap of left edge of region to output.

       int y (in)			    Y-coordinate within bitmap of top edge of region to output.

       int width (in)			    Width of region of bitmap to output, in pixels.

       int height (in)			    Height of region of bitmap to output, in pixels.

       XColor *colorPtr (in)		    Information about color value to set in Postscript.

       Tk_Font tkFont (in)		    Font for which Postscript is to be generated.

       double *coordPtr (in)		    Pointer  to an array of coordinates for one or more points specified in canvas coordinates.  The order
					    of values in coordPtr is x1, y1, x2, y2, x3, y3, and so on.

       int numPoints (in)		    Number of points at coordPtr.
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DESCRIPTION

       These procedures are called by canvas type managers to carry out common functions related to generating Postscript.  Most of the procedures
       take a canvas argument, which refers to a canvas widget for which Postscript is being generated.

       Tk_CanvasPsY  takes  as	argument  a  y-coordinate in the space of a canvas and returns the value that should be used for that point in the
       Postscript currently being generated for canvas.  Y coordinates require transformation because Postscript uses an origin at the	lower-left
       corner whereas X uses an origin at the upper-left corner.  Canvas x coordinates can be used directly in Postscript without transformation.

       Tk_CanvasPsBitmap generates Postscript to describe a region of a bitmap.  The Postscript is generated in proper image data format for Post-
       script, i.e., as data between angle brackets, one bit per pixel.  The Postscript is appended  to  interp->result  and  TCL_OK  is  returned
       unless an error occurs, in which case TCL_ERROR is returned and interp->result is overwritten with an error message.

       Tk_CanvasPsColor  generates  Postscript	to set the current color to correspond to its colorPtr argument, taking into account any color map
       specified in the postscript command.  It appends the Postscript to interp->result and returns TCL_OK unless an error occurs, in which  case
       TCL_ERROR is returned and interp->result is overwritten with an error message.

       Tk_CanvasPsFont generates Postscript that sets the current font to match tkFont as closely as possible.	Tk_CanvasPsFont takes into account
       any font map specified in the postscript command, and it does the best it can at mapping X fonts to Postscript fonts.  It appends the Post-
       script  to  interp->result and returns TCL_OK unless an error occurs, in which case TCL_ERROR is returned and interp->result is overwritten
       with an error message.

       Tk_CanvasPsPath generates Postscript to set the current path to the set of points given by coordPtr and numPoints.  It appends the  result-
       ing Postscript to interp->result.

       Tk_CanvasPsStipple generates Postscript that will fill the current path in stippled fashion.  It uses bitmap as the stipple pattern and the
       current Postscript color;  ones in the stipple bitmap are drawn in the current color, and zeroes are not drawn at all.  The  Postscript	is
       appended  to interp->result and TCL_OK is returned, unless an error occurs, in which case TCL_ERROR is returned and interp->result is over-
       written with an error message.

KEYWORDS

       bitmap, canvas, color, font, path, Postscript, stipple

Tk									4.0							    Tk_CanvasPs(3)