It's very important that you read this introduction if you've never used this software before. After reading it, you'll know all the prerequisites for starting the application in your machine.
 
 

Executable Location and Desktop Icons

You can choose to either start the executable with the UNIX shell, or with the IRIX Interactive Desktop. After installation, the application executable is at '/usr/pegamento/'. Its Desktop icon is placed in the 'Applications' page of the 'Icon Catalog' (read the end of 'Help>UserInterface' to learn about the Pegamento desktop icons).
 
 

IRIX Prerequisites

* IRIX 6.2 or higher.

* The executable is "n32". This is not a problem for IRIX 6.3 and later, where "n32" support is installed by default. However, IRIX 6.2 doesn't install "n32" components by default. You've to manually install it from the IRIX CDs. Be sure that your IRIX installation is ready for running n32 applications. If you get 'rld' fatal errors when starting the application, check that you installed all the 'sw32' (n32) subsystems from the IRIX CDs.

* Your system must have the "n32" subsystem of the SGI IFL ("Image Format Library Execution Only Environment") installed, or the application won't start up. Such product is in the IRIX CDs, but can also be found at the SGI webpage, and you can freely download it.

* If you run IRIX 6.2, 6.3, or 6.4, you must install the latest IRIX complete patchset, available from http://support.sgi.com. Check that all the 'sw32' (n32) subsystems from the patches are installed, as they might not be installed by default (specially if you run 6.2). In the case of 6.2 and 6.3, you may suffer some important graphics and X11 bugs if you don't install the latest complete patchset. At the time of writing this, Pegamento has not been tested with 6.4, but it's very likely that you should also install the complete patchset as well.

* If your machine is an Indigo2 IMPACT under IRIX 6.2: It's very important that you check you installed the "Graphics N32 Execution Environment" subsystem from the 3133 patch, because such subsystem is not installed by default, and you really need it for a successful operation of n32 graphics applications. Otherwise, the applications could behave wrongly or even crash. In order to check you installed it, open the "Software  Manager", scroll down until you see the "Patch SG0003133: Indigo2 Impact Bug Fix for IRIX 6.2", and click on its left icon in order to see if the N32 subsystem is actually installed. Otherwise, you'll need to explicitly install it.

* If you run IRIX 6.2, 6.3, or 6.4, check that your C and C++ runtimes are updated enough for running executables built with the MIPSpro release used to build Pegamento (usually either MIPSpro 7.3 or 7.1). If not, you must update your runtimes with patches. These patches must usually be individually downloaded from http://support.sgi.com, because they're usually not included in patchsets.
 
 

Hardware Requisites

A Silicon Graphics workstation or visualization supercomputer with the following specs:

* Capable of running MIPS-III or MIPS-IV code (depending on the executable version you downloaded). This means either a R4X00, R5X00, R8000 or R1X000 MIPS processor.

* Three-button mouse. All the three buttons are necessary for using the application. There're no keyboard workarounds at this moment.

* Texture memory:       The most valuable resource in the tool.
* Alpha (RGBA visuals): Optional, but required for matte layers.
* Pixel buffers:        Optional, but required for final rendering.
* 12+12+12+12 color:    Optional, will enhance color quality.
* Double buffer:        Optional, will avoid flickering.
* Overlay:              Optional, for dialogs and menu panes.
(Note: neither stencil nor depth buffers are allocated).

* System RAM: Less important than texture memory (except in UMA machines like the O2). However, if your machine has little texture memory (like 4MB), it will perform "TRAM swapping" unless your layers are small or unless you enable Low-Res mode, so system RAM will be used as a temporal storage for textures, and you'll need RAM enough for that. When doing final rendering, note that the output image is temporarily allocated in system RAM just before saving it to disk, so you'll need RAM enough for your rendering size.
 
 

Example Workstations

Older Extreme, XZ, Elan, and so on are generally not suitable for this application, because they don't support textures in hardware, they also lack RGBA visuals (they support RGB only), and they don't support Pixel Buffers. In other words, you can't do final rendering, you can't use matte layers, and image layers will be very slow. The only use is if you just create DXF and Bézier layers and you don't do mattes nor final rendering. So, very limited.

The O2 is great (virtually unlimited texture memory), although it lacks 12+12+12+12 color, and its limited pixel-fill usually creates speed bottlenecks when many layers are located on top of each other in the same area. Despite of this, it's a very good machine for the application, because you don't have to worry about image size (provided that you've RAM enough), and the ICE provides good acceleration for image processing filters. If you want to use very large images, the O2 is perhaps the best desktop choice.

Indigo2 High/Maximum IMPACT (and Octane+Texture) are also good performers (and they support 12+12+12+0 color if you don't use matte layers, or 8+8+8+8 otherwise). Check that you have the 4MB TRAM option installed (IMPACT with just 1MB TRAM just supports 16bit textures, which don't provide quality enough for proper use of Pegamento). Read the documentation about the Texture LOD Optimization and the Low Resolution Mode (at 'Help>ImageLayers'), because it's very useful for IMPACT and Octane users. If your image layers fit in the 4MB TRAM, these machines are better than the O2, because their pixel-fill performance and their image processing acceleration (GE11 Geometry and Imaging Engines) is faster than the O2 ICE and MRE. However, when you begin using 8MB or more of image layers, the O2 usually wins, although the previously mentioned optimizations can keep a very good performance in IMPACT machines, when properly used.

Octane2 and Fuel are likely to be very good performers, although it has not been deeply tested yet (except for demo-ing TexelDesk, the predecessor of Pegamento, on a V12 Octane2). In the case of V8/V12, which support 108MB of textures, it might be very hard for the O2 to win against them, even if you use very large image layers. Anyway, in this moment this is just theory, as it has not been tested.

Visualization supercomputers (Onyx-class) should be a very good choice for this application (specially InfiniteReality-4, with 1GB-TRAM support), but, like in the VPro case, they've not been tested yet.
 
 

Tested Machines

These are the machines which have been deeply tested, and that are suitable for using all features implemented in Pegamento. If your machine is not listed, it just means that it has not been tested yet (or that it's been tested by other users and I don't know how deeply they did the test). But it doesn't mean that you cannot use such machine.

The list is quite limited. There's no "official test suite" to determine whether a machine is qualified or not. If you're able to successfully finish a compositing work with Pegamento, please report your machine model, configuration, and IRIX version, and I'll add it to the list:

O2 R5000SC-180MHz, IRIX 6.3 fully-patched, in 32+32 1280x1024 mode.

O2 R5000SC-180MHz, IRIX 6.5.15m, in 32+32 1280x1024 mode.

Indigo2 HighIMPACT 4MB-TRAM R4400-200MHz, IRIX 6.2 fully-patched, with '1280x1024_76', '1024x768_76', and '1024x768_76_pbuf' setmon framebuffer configurations.
 
 

Overlay Dialogs

If your machine has 4 or more overlay bits (which is true for most Silicon Graphics systems), dialog boxes will be created in overlay. This lets you drag dialog windows without trashing the main view (and so without needing to redraw it, resulting in smooth dragging of dialogs).

This advantage is most noticeable if your IRIX desktop has the "Opaque Window Move" setting enabled (it's located in your IRIX desktop at 'Toolchest>Desktop>Customize>Windows'), resulting in very smooth and fast dragging of your dialog windows when they're created in overlay, like Pegamento does.

It also has a drawback, though: No matter how many overlay bits your machine has, the dialog window borders will be just 1-bit monochrome. However, the contents of dialog boxes take advantage of all the available overlay bits, so the more overlay bits you have, the higher quality your dialog GUI controls will get).
 
 

Silicon Graphics Framebuffer Configuration

Check that the framebuffer is properly configured in your workstation (with either 'xsetmon', 'setmon', or 'xscreen', depending on your workstation and IRIX version). The default settings are often fine for Pegamento, except for O2 users (which you should configure as 32+32 for proper quality), and perhaps HighIMPACT users (who, depending on the situation, may prefer to use 1024x768 resolution in order to be able to get double buffered 32bit RGBA color).

If your workstation is an O2, it's VERY IMPORTANT THAT YOU CONFIGURE YOUR FRAMEBUFFER AS 32+32.

The optimum screen resolution for which the user interface is designed is 1280x1024. It's also usable at 1024x768, but no lower than that. If running at 1024x768, you'll need to hide the window title with the 'File>Settings' submenu and maximize the window in order to be able to use the 'Layer Stack' list. Remember that you can still manage the window when the title is hidden by simultaneously pressing the left Alt key and the right mouse button. The 1024x768 resolution might be useful for HighIMPACT users, because such workstation models support double buffered 32bit color together with a 32bit pbuffer only when running at 1024x768. This doesn't affect MaximumIMPACT users, as they've more framebuffer memory. Note that Pegamento is not usable for resolutions lower than 1024x768. Resolutions higher than 1280x1024 should be usable, but they've not been tested.
 
 

Checking Start-Up Results

Open the 'Render>FramebufferInfo' dialog window. It will tell you the RGBA bits of the main view and the Pixel Buffer, as well as whether the main view is double buffered or not.

If you get a result such as this, your machine is optimal for working with the application:

              Width  Height  R  G  B  A  Double
Window          --      --   8  8  8  8    1
Pixel Buffer   576     576   8  8  8  8    0
 
 

Warnings at Start-Up

When you start the application, a dialog window with a warning message may appear if it wasn't possible to allocate framebuffer resources of the quality required for proper operation. Depending on your machine, you may be able to fix these warnings by changing the framebuffer configuration (see above section), or with command-line arguments (see 'Help>CommandLineArguments'). But if the source of the problem is a hardware limitation rather than a non-optimal setup, you won't be able to get rid of these warnings.

* "Interactive View has no alpha channel... Mattes won't work in the interactive view."

* "Interactive View has no double buffer... You'll experience flickering in the interactive view."

* "Interactive View has very few alpha bits... Mattes will be very inaccurate in the interactive view."

* "Interactive View has less than 8+8+8 RGB bits... Color banding may appear in the interactive view."

* "Interactive View has less than 8 alpha bits... Mattes will be inaccurate in the interactive view."

* "There's no Pixel Buffer. Final rendering not available. Read about the pixel buffer command line options in the Help menu."
 
 

Tips For HighIMPACT Users

If you run the application on a HighIMPACT at 1280x1024, you'll get a double-buffered 16-bit 4+4+4+4 RGBA main view. If you want 32bit 8+8+8+8, you must either start Pegamento in single buffered mode ('-wsingle' argument, see 'Help>CommandLineArguments'), or change the framebuffer configuration to 1024_768_76, which will allow you double buffered 8+8+8+8, as well as double buffered 12+12+12+0.

Also, if the Pixel Buffer can't be allocated (you can check it with the 'Render>FramebufferInfo' dialog window), check that other graphics applications are not running when you start Pegamento. If you still can't allocate a Pixel Buffer, change your 'setmon' framebuffer configuration. It IS possible to allocate a 8+8+8+8 Pixel Buffer on HighIMPACT machines. You can even allocate a 12+12+12+0 Pixel Buffer if you use the '1024x768_76_pbuf' setmon configuration and some command-line arguments (this is explained at 'Help>ColorPrecision').

Regarding performance, don't forget to read 'Help>ImageLayers', because some of the optimizations discussed there can be very noticeable in IMPACT machines.