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blt::winop(3tcl) BLT Built-In Commands blt::winop(3tcl)


winop - Perform assorted window and image operations


winop changes window

winop gradients leftcolor rightcolor gradients

winop image subcommand ...

winop image alpha srcImage destImage color

winop image colors ?-alpha? srcImage

winop image convolve srcImage destImage filter

winop image gradient image leftcolor rightcolor ...

winop image merge srcImage1 srcImage2 destImage ?alpha? ?...?

winop image mirror srcImage1 destImage ?x|y|xy|tile|outer|inner?

winop image quantize srcImage destImage ?nColors?

winop image readjpeg filename photoname

winop image resample srcImage destImage ?horizFilter? ?vertFilter?

winop image rotate srcImage destImage angle

winop image subsample srcImage destImage x y width height ?horizFilter? ?vertFilter?

winop lower ?window?...

winop map ?window?...

winop move window x y

winop query

winop raise ?window?...

winop snap window photoName ?width height ?

winop unmap ?window?...

winop warpto ?window?


The winop command performs various window and image operations on Tk windows using low-level Xlib function calls to work around window manager pecularities.


Tk has several commands for manipulating its windows: raise, lower, wm, etc. These commands ask the window manager to perform operations on Tk windows. In some cases, a particular window manager won't perform the operation as expected.

For example, if you positioned a toplevel window using wm geometry, the window may not actually be at those particular coordinates. The position of the window may be offset by dimensions of the title bar added by the window manager.

In situations like these, the winop command can be used to workaround these difficulties. Instead, it makes low-level Xlib (such XRaiseWindow and XMapWindow) calls to perform these operations.

toplevel .top
wm withdraw .top
# Set the geometry to make the window manager 
# place the window.
wm geometry .top +100+100
# Move the window to the desired location
# and "update" to force the window manager
# to recognize it.
winop move .top 100 100
wm deiconify .top
winop move .top 100 100


The following operations are available for the winop command:

Realize window.
Image sub-commands.
Set image pixels of the given color to transparent. If an alpha value is not given, it defaults to 0 (meaning transparent). An alpha of 255 is used for solid. The srcImage and destImage may be the same. If the color is * any color is matched. If color is prefixed with ! match is inverted.
Return a list of width colors that graduate from leftcolor to the color just before rightcolor. Note that the last color in the returned list is not rightcolor. A typical use for this is calculating shadow colors.
Blur an image using gaussian blur.
Return list of distinct colors. If -alpha is given, the alpha is appended to each color after a colon, eg #FF0000:00. If -count is given, returns color/count pairs.
Convolve an image: filter is a list of numbers. The srcImage and destImage may be the same.
Generate a gradient from left to right into image. The following options are available:
Set the type of gradient. The default is sine.
The skew determines the initial fraction of the image that the gradient occupies, after which only rightcolor is used. The skew must be > 0 and <= 1.0. The default value is 1.0, meaning not skewed.
Make the gradient slant where a value of 1.0 slants at 45 degrees. The value must be between -100.0 and 100.0.
Curve the gradient by passing the Y position to the function -mathfunc. The value must be between -100.0 and 100.0 (typically 1.0). The default is 0.0, which means disabled.
Function to use with -mathval. The default value is sin. The value must be one of: sin cos tan sinh cosh tanh asin acos atan log log10 exp sqrt rand circle.
Add small random purturbations to gradient to avoid striation lines. The value must be between 0.0 and 0.1.
Change the image height.
Change the image width.
Merge two images with alpha blending. The default ?opacity? is 0.5, and the default for ?opacity2? is 1.0 - ?opacity?.
Flips an image on axis x, y or xy. The tile option results in a double size image with mirror copies appended to generate a tile-able image. The outer option is used to resize an image while preserving the outside border by halo pixels (default is 16). The inner option copies from the center of source keeping it centered. These last 2 are used implicitly by blt::tile::button -bdtile, etc. The srcImage1 and destImage must not be the same if using tile, inner or outer. The default is xy.
Limit number of colors in image. Default 1. The srcImage and destImage may be the same.
Read a jpeg image using libjpeg. IMG makes this obsolete (and thus probably not builtin).
Change pixels from oldColor to newColor. If ?alpha? is not given it defaults to 255 (opaque). The srcImage and destImage may be the same.
Resample an image. If srcImage and destImage are the same size, just makes a copy. Otherwise the image is resized to the size of destImage, possibly wih filtering. Filters are one of: bell bessel box bspline catrom default dummy gauss8 gaussian gi lanczos3 mitchell none sinc triangle. The destImage must be greater than 1x1.
Rotate an image. The srcImage and destImage may be the same.
Resample area of an image. See resample.
Get or set the integer alpha value within an image.
Lowers window to the bottom of the X window stack. Window is the path name of a Tk window.
Maps window on the screen. Window is the path name of a Tk window. If window is already mapped, this command has no effect.
Move window to the screen location specified by x and y. Window is the path name of a Tk window, while x and y are screen coordinates. This command returns the empty string.
Query pointer position. Returns @X,Y.
Raises window to the top of the X window stack. Window must be a valid path name of a Tk window. This command returns the empty string.
Takes a snapshot of the window and stores the contents in the photo image photoName. Window is the valid path name of a Tk window which must be totally visible (unobscured). PhotoName is the name of a Tk photo image which must already exist. This command can fail if the window is obscured in any fashion, such as covered by another window or partially offscreen. In that case, an error message is returned. If width or height is given, the image is resampled to the given size.
Unmaps window from the screen. Window is the path name of a Tk window.
Warps the pointer to window. Window is the path name of a Tk window which must be mapped. If window is in the form @x,y, where x and y are root screen coordinates, the pointer is warped to that location on the screen.

[I've never heard a good case for warping the pointer in an application. It can be useful for testing, but in applications, it's always a bad idea. Simply stated, the user owns the pointer, not the application. If you have an application that needs it, I'd like to hear about it.]

If no window argument is present the current location of the pointer is returned. The location is returned as a list in the form "x y", where x and y are the current coordinates of the pointer.


window, map, raise, lower, pointer, warp

2.5 BLT