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An Introduction to Script Editor

In this chapter we will explore the power and functions of MEL script editor.

Rated: with 278 hits  Added on: Apr 15, 2008

The MEL Command Syntax

The most fundamental aspect of MEL is command. In this chapter we will gain understanding of MEL commands.

Rated: with 233 hits  Added on: Apr 15, 2008

Maya Prompt

When you open the Maya, it first runs plenty of scripts that actually builds all the interface windows and elements you see. Maya itself has no interface. You can use Maya without using its interface. In this chapter we will discuss about the Maya Prompt and use it to create a Maya file.

Rated: with 209 hits  Added on: Apr 15, 2008

Values & Variables

Variable is essentially a placeholder for data. Once we store data in the placeholder we manipulate and change the value of that data, whenever we want to. In this chapter we will explore variables deeply.

Rated: with 140 hits  Added on: Apr 15, 2008

An Introduction to Programming Concepts

In this chapter we will examine the process and techniques to control the flow of the script. Loops let us repeat a command over and over. Loops check a condition and then continuously loop as long as condition stands true. Before we dig deep into looping, let us first understand how to test and compare values in MEL.

Rated: with 156 hits  Added on: Apr 15, 2008

Attributes

Attribute (MEL term Attr) is any item that lives inside the Maya node. In this chapter we will learn commands like listAttr, setAttr and getAttr.

Rated: with 199 hits  Added on: Apr 15, 2008

The Style

Your scripts should be neat, elegant, boolet-proof and properly included comments. This chapter is about Style of MEL script.

Rated: with 149 hits  Added on: Apr 15, 2008

MEL Script Nodes

MEL allows scripters to save maya scripts inside of Maya file. In this chapter we will create and explore MEL script nodes.

Rated: with 211 hits  Added on: Apr 15, 2008

Hello Mr. OS

system command executes commands from the shell. The output of the executed command is returned as string. This command is used to execute OS commands. In this chapter we will examine the system command and build a backup system using winzip.

Rated: with 175 hits  Added on: Apr 15, 2008

Uninstancer Mel Script for Maya

The Uninstancer Mel Script for Maya allows you to bake particle instances into geometry, animation, and blendshapes that can be modified and updated without messing around with dynamics and expressions.

Rated: with 507 hits  Added on: Mar 04, 2008

How to sample color at any given point in a ramp

From our website: www.tjgalda.com Skill level: intermediate How do you query the colour in a ramp at any given point? Frustratingly, this isnt quite as simple as it sounds. Even the technical documentation from Autodesk states: Currently the routines to get the value of a ramp structure (with interpolation) are not available through MEL, which limits the use of this control by end users. So, we have to work around it in this case. We are able to sample the ramp and get back i)how many colour entries there are, ii)where they are in the ramp and iii) what colour they are. From that data, we can approximate fairly well what the ramp looks like. Lets build the tool for our example to do so on a relatively simple scale. You can add complexity later, but to keep things simple, were going to sample a simple ramp with two colours and a linear interpolation between the two colours. A ramp such as this mel code will create: Note: you can view all the mel on the website. www.tjgalda.com Create the gradient using a ramp: string $tempName = `shadingNode -asShader ramp`; string $tj_rampNode = `rename $tempName tj_gradientColour`; string $tj_rampWin = `window -t tj Ramp Viewer tj_rampWin`; columnLayout; rampColorPort -node $tj_rampNode; showWindow $tj_rampWin; setAttr ($tj_rampNode + .colorEntryList[0].color) -type double3 0.988 1 0.8 ; setAttr ($tj_rampNode + .colorEntryList[1].color) -type double3 0 0 0.235 ; setAttr ($tj_rampNode + .colorEntryList[1].position) 1.0; removeMultiInstance -break true ($tj_rampNode + .colorEntryList[2]); showWindow $tj_rampWin; Now that we have the ramp, we can gather information about the ramp. We need to determine where are they and what colour, create an array to catch each position and match the entry in the list of the ramp. Finally we will create an array to catch colour, use a vector array to maintain match in the list of the ramp. Where are they and what colour? Create an array to catch each position and match entry in list. int $entries = `getAttr -size ($tj_rampNode+.colorEntryList)`; vector $entry_colour[]; for ($i = 0; $i < $entries; $i ++) { $entry_pos[$i] = `getAttr ($tj_rampNode+.colorEntryList[+$i+].position)`; float $entryList_colours[] = `getAttr ($tj_rampNode+.colorEntryList[+$i+].color)`; $entry_colour[$i] = >; } //and print back the results print ("n$entry_pos[] is n==================n"); print $entry_pos; print ("nn==================n$entry_colour[] is n==================n); print $entry_colour; $entry_pos[] is ================== 0 1 ================== $entry_colour[] is ================== 0.988 1 0.8 0 0 0.235 In our example now, we can see that we have the two colour entries at 0 and 1, with the associated colour mix. Now we can work with some basic calculations to deduce what the colours are between. After we know the colour information, we can then begin to deduce what the ramp is like. The first step is to find the difference or delta between the two colours on each channel. From there, we can divide up the colour on regular intervals and determine what the exact colour is at any specific point on the map. This is a sampling step. How many intervals should we break the ramp into? int $step = 20; Find the delta/difference for each channel. Use temp vectors to get data out of the array easily. For our example to keep it simple, we can make some assumptions about where each entry is and what colours they are. We will assume only two colours, and that the first colour is brighter. Of course, one should build in robustness to remove these assumptions with true data. vector $tempTopV = $entry_colour[0]; vector $tempBotV = $entry_colour[1]; Use absolute to ensure its not a negative value float $differenceR = `abs($tempTopV.x - $tempBotV.x)`; float $differenceG = `abs($tempTopV.y - $tempBotV.y)`; float $differenceB = `abs($tempTopV.z - $tempBotV.z)`; Divide up the delta per step. This is the amount of change per step that each colour travels. float $deltaStepR = $differenceR / $step; float $deltaStepG = $differenceG / $step; float $deltaStepB = $differenceB / $step; Now, start number + (delta per step * the number of steps) = end number, in other words, we have broken down what the difference can be at each interval. Finalize by building the arrays. float $colourStepsR[], $colourStepsG[], $colourStepsB[]; $colourStepsR[0] = $tempBotV.x; $colourStepsG[0] = $tempBotV.y; $colourStepsB[0] = $tempBotV.z; Each new step is the old step + the delta for that colour. for ($i = 1; $i

Rated: with 439 hits  Added on: Nov 20, 2007

How to make a fun pause screen using mel

From our website: http://www.tjgalda.com How to make a fun pause screen using mel. - TJ Galda, CG Supervisor There are times when you may need to create a pause screen to entertain the users while you fetch something or do some work in the background. This is probably one of the more interesting times that you can make use of a gradient. This tutorial will show you how to create a screen that slowly turns green as the job is completed. Once the designated pause time is done, the window goes away and returns control to the user. The first step is to create a gradient or ramp node: //Create the gradient using a ramp: string $tj_tempName = `shadingNode -asShader ramp`; string $tj_rampNode = `rename $tj_tempName "tj_gradientColourTemp"`; After that, we need to set up colours. Were using a black ramp that fills to green, so we need three colours. A black to fill, a green to go to, and one that makes the transition. setAttr ($tj_rampNode + ".colorEntryList[0].color") -type double3 0.2 1 0.2 ; setAttr ($tj_rampNode + ".colorEntryList[1].color") -type double3 0.2 0 0.2 ; setAttr ($tj_rampNode + ".colorEntryList[2].color") -type double3 0 0 0.2 ; setAttr ($tj_rampNode + ".colorEntryList[0].position") 0.0; setAttr ($tj_rampNode + ".colorEntryList[1].position") 0.0; setAttr ($tj_rampNode + ".colorEntryList[2].position") 1.0; After that, we need to create a window and display the ramp to the user. //create window string $tj_winName = "tj_winName"; string $tj_winTitle = "TJ Fun Pause Screen"; if ( `window -exists $tj_winName` ) deleteUI -window $tj_winName; string $tj_rampWin = `window -t $tj_winTitle -wh 258 258 $tj_winName`; columnLayout; rampColorPort -node $tj_rampNode; showWindow $tj_rampWin; Now we need to take control away from the user, and have something happen. As shown above, we achieve this by having our ramp slowly change from black to green and fill in. It can be all done with a simple loop. By slicing the counter smaller and smaller, the pause will increase. As noted in the comments below, were using a slice of 0.005. //do timer by filling in ramp with greenfloat $tj_i = 0.0; while ($tj_i < 1) { float $tj_newPos = $tj_i; setAttr ($tj_rampNode + ".colorEntryList[1].position") $tj_newPos; setAttr ($tj_rampNode + ".colorEntryList[1].color")0.2 $tj_newPos 0.2 ; // the smaller this increment, the longer the pause // using 0.005 tends to get us in around 15 seconds $tj_i = $tj_i + 0.005; showWindow $tj_rampWin; } Thats all there is too it. All we have left is to clean up what weve done. Delete the window and ramp nodes: ///////////////////////////////////// // 15 seconds passed, all done pausing //kill window if ( `window -exists $tj_winName` ) deleteUI -window $tj_winName; //delete ramp delete $tj_rampNode; print "n -=-=-=-= Finished pause screen. =-=-=-=- n"; //done More tutorials also available at our website: http://www.tjgalda.com .

Rated: with 347 hits  Added on: Nov 20, 2007

Object spreading methods using Maya

This article demonstrates five methods to spread objects in maya from author's own experience/analysis and some talking boards threads.

Rated: with 764 hits  Added on: Oct 07, 2007

Making a Blizzard

This tutorial will show you how to make simple blizzard in Maya using particle instancer. Before starting this tutorial its good idea to look at mine previous tutorials about particle instancers.

Rated: with 1492 hits  Added on: Jul 17, 2007

Making Tank Treads using AS_TreadsCreation script

Ever wondered how to make tank treads? There’s no easy way. But there is help, and here it is.

Rated: with 2110 hits  Added on: Jul 02, 2007

Fast Puffy Type Explosions in Maya

This tutorial will show how to make simple puffy explosion using fluids in Maya. It will explode and than give off black smoke.

Rated: with 2500 hits  Added on: Jun 02, 2007

Expressions

this tutorial is very handy to create, explosions like tank explosion, asteroid explosions

Rated: with 1908 hits  Added on: Mar 01, 2007

mel ShapeEditor

In this tutorial I will go through how I created the final3 multiple shapeEditor.

Rated: with 1455 hits  Added on: May 24, 2006

Maya Expressions 2

Maya Expressions 2

Rated: with 2457 hits  Added on: Apr 14, 2006

Maya Expressions 1

An introduction to the basics of using expressions in Maya. This tutorial shows how to make simple wings flap at a controllable speed without setting a single keyframe. Also see Maya Expressions 2

Rated: with 4682 hits  Added on: Apr 14, 2006