This is version 4.0 of the BLT library. It's an extension to the Tcl/Tk toolkit. You simply compile and link with the Tcl/Tk libraries. It does not require the Tcl or Tk source files. BLT is available from www.sourceforge.net/projects/blt/files This release has been built and tested with the following Tcl/Tk versions: Tcl/Tk 8.0 thru 8.6 Tcl 7.6/Tk 4.2 isn't supported any more. If you need Tcl 7.x, use the 2.4z release. What is BLT? BLT is an extension that adds new widgets and commands to Tcl/Tk. It adds plotting widgets (X-Y graph, barchart, stripchart), a powerful geometry manager, a new canvas item, tree and table data objects. Plotting widgets: blt::graph, blt::barchart, blt::stripchart BLT has X-Y graph, barchart, and stripchart widgets that are both easy to use and customize. All the widgets work with BLT vector data objects, which makes it easy to manage data. Tree viewer blt::treeview Displays a general ordered tree which may be built on-the-fly or all at once. blt::tree Tree data object. blt::datatable blt::tableview Tab set: blt::tabset Can be used either as a tab notebook or simple tabset. Multi-tiered and/or scrolled tabsets are available. Notebook pages can be torn-off into separate windows and later put back. Geometry Managers: blt::table A table-based geometry manager. Lets you specify widget layouts by row and column positions in the table. Unlike the packer or grid, you can finely control and constrain window sizes. blt::paneset blt::filmstrip blt::drawerset blt::scrollset blt::combobutton blt::comboeditor blt::comboentry blt::combomenu blt::combotree Vector Data Object: blt::vector Lets you manage a vector of floating point values in a high-level fashion. Vectors inter-operate seamlessly with the plotting widgets. The graphs will automatically redraw themselves when the vector data changes. Vector's components can be managed through a Tcl array variable, a Tcl command, or the using its own C API. Background Program Execution: blt::bgexec Like Tcl's "exec ... &", but collects the output, error, and status of the detached UNIX subprocesses. Sets a Tcl variable upon completion. Busy Command: blt::busy For preventing user-interactions when the application is busy. Manages an invisible "busy" window which prevents further user interactions (keyboard, mouse, button, etc.). Also you can provide a busy cursor that temporarily overrides those of the Tk widgets. New Canvas Item: eps An new item is added to the Tk canvas for handling encapsulated PostScript. It lets you embed an EPS file into the canvas displaying either an EPS preview image found in the file, or a Tk image that you provide. When you print the canvas the EPS item will automatically include the EPS file, translating and scaling the PostScript. For example, you could use "eps" items to tile several PostScript pages into single page. The "eps" item can also be used as a replacement for "image" canvas items. Unlike "image" canvas items, the image of an eps item can be printed and scaled arbitrarily. Drag & Drop Facility: blt::drag&drop Adds drag-n-drop capabilities to Tk. It uses "send"-style communication between drag-drop sources and targets. The result is a much more powerful drag-and-drop mechanism than is available with OpenLook or Motif. Bitmap Command: blt::bitmap Lets you read and write bitmaps from Tcl. You can define bitmaps from ordinary text strings. Bitmaps can also be scaled and rotated. For example, you can create a button with rotated text by defining a bitmap from a text string and rotating it. You can then use the bitmap in the button widget. Miscellaneous Commands: blt::winop Basic window operations. You can raise, lower, map, or, unmap windows. Other operations let you move the pointer or take photo image snapshots of Tk widgets. blt::debug Lets you trace the execution of Tcl commands and procedures. Prints out each Tcl command before it's executed. blt::watch Lets you specify Tcl procedures to be run before and/or after every Tcl command. May be used for logging, tracing, profiling, or debugging or Tcl code. blt::spline Computes a spline fitting a set of data points (x and y vectors) and produces a vector of the interpolated images (y-coordinates) at a given set of x-coordinates. blt::htext A simple hypertext widget. Allows text and Tk widgets to be combined in a scroll-able text window. Any Tk widget can be embedded and used to form hyper-links. Other options allow for selections and text searches. How to compile and test BLT? See the file "INSTALL" for instructions. Does BLT work under Windows? Yes. Windows 95/98/ME/NT/2000/XP. I've compiled it with both MS VC++ 5.0/6.0p4 and EGCS 1.1.1. Self-installing pre-compiled versions are available. What are the differences between the Windows and Unix releases? All commands work: graphs, bgexec, busy, drag&drop etc. except the "container", and "cutbuffer" widgets. The "drag&drop" command still needs to use "send" to transfer information between Tk applications. You can use ./demos/scripts/send.tcl to imitate "send" using DDE. Just source the script and execute SendInit SendVerify to set up the new send command. When will...? In general, I can't answer the "When will" questions, mostly out of embarrassment. My estimates of when new features and releases will occur usually turn out to be way way off. What does BLT stand for? Whatever you want it to. Where to send bugs reports, suggestions, etc. ? gahowlett@gmail.com Make sure you include BLT and the version number in the subject line. --gah