'\"
'\" Generated from file 'canvas_gradient\&.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 2013 Jarek Lewandowski, MaxJarek
'\" Copyright (c) Origin http://wiki\&.tcl\&.tk/6100
'\" Copyright (c) Origin http://wiki\&.tcl\&.tk/37242
'\" Copyright (c) Origin http://wiki\&.tcl\&.tk/9079
'\"
.TH "canvas::gradient" 3tk 0\&.2 tklib "Variations on a canvas"
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.SH NAME
canvas::gradient \- Canvas with a gradient background
.SH SYNOPSIS
package require \fBTcl  8\&.5\fR
.sp
package require \fBTk  8\&.5\fR
.sp
package require \fBcanvas::gradient  ?0\&.2?\fR
.sp
\fB::canvas::gradient\fR \fIpathName\fR ?options?\&.\&.\&.
.sp
.BE
.SH DESCRIPTION
This package provides a command to set background gradients on canvases\&.
.PP
\fINOTE!\fR This package reserves the canvas tag
\fBcanvas::gradient\fR for its use\&.
.SH API
.TP
\fB::canvas::gradient\fR \fIpathName\fR ?options?\&.\&.\&.
Creates a background gradient on the canvas \fIpathName\fR\&.
An existing gradient is replaced by the new definition\&.
.sp
The set of available options is decribed below, in
section \fBOptions\fR\&.
.PP
.SS OPTIONS
.TP
\fB-direction\fR \fIdirection\fR
The value for this option specifies the \fIdirection\fR of the gradient\&.
If not specified the system defaults to \fBx\fR, a horizontal gradient\&.
The package supports five directions:
.RS
.TP
\fBx\fR
for a horizontal gradient (default)\&.
Color changes along the x-axis,
with the start color at the left\&.
.TP
\fBy\fR
for a vertical gradient\&.
Color changes along the y-axis,
with the start color at the top\&.
.TP
\fBd1\fR
for a diagonal gradient from left+top to bottom+right\&.
Color changes along the diagonal\&.
with the start color at left+top\&.
.TP
\fBd2\fR
for a diagonal gradient from left+bottom to top+right\&.
Color changes along the diagonal\&.
with the start color at left+bottom\&.
.TP
\fBr\fR
for a radial gradient around the center of the viewport
Color changes from the center outward,
with the start color at the center\&.
.RE
.TP
\fB-color1\fR \fIcolor\fR
The value for this option specifies the starting color of the gradient\&.
If not specified it defaults to \fBred\fR\&.
.TP
\fB-color2\fR \fIcolor\fR
The value for this option specifies the ending color of the gradient\&.
If not specified it defaults to \fBgreen\fR\&.
.TP
\fB-type\fR \fItype\fR
The value for this option specifies how the gradient is calculated\&.
The package currently supports on ly one method, which is the
default, naturally:
.RS
.TP
\fBlinear\fR
for linear interpolation between the start and end colors (default)\&.
.RE
.PP
.SH EXAMPLE
.CS


	package require canvas::gradient
	canvas \&.c
	canvas::gradient \&.c -direction x -color1 yellow -color2 blue
	pack \&.c -fill both -expand 1

.CE
.SH "BUGS, IDEAS, FEEDBACK"
This document, and the package it describes, will undoubtedly contain
bugs and other problems\&.
Please report such in the category \fIcanvas\fR of the
\fITklib Trackers\fR [http://core\&.tcl\&.tk/tklib/reportlist]\&.
Please also report any ideas for enhancements you may have for either
package and/or documentation\&.
.SH KEYWORDS
background, canvas, color gradient, gradients, image, widget background
.SH COPYRIGHT
.nf
Copyright (c) 2013 Jarek Lewandowski, MaxJarek
Copyright (c) Origin http://wiki\&.tcl\&.tk/6100
Copyright (c) Origin http://wiki\&.tcl\&.tk/37242
Copyright (c) Origin http://wiki\&.tcl\&.tk/9079

.fi