One way that I am currently developing is a POVray include based on Blobman, adapted to L3P's output (using what Friedrich Lohmueller describes here). More here.
This is a work in progress. Here is how it works so far:
1. Create a Ldraw file with a minifig. Currently, the m_walk include will accept all parts used by the Minifig Generator found in Mlcad. (I've used Willy Tschager's mlcad.ini file). The include is not yet meant to work with any accessories other than hat parts.
2. Use L3P to generate a POV scene which includes the minifig you've just create. DO NOT RENDER THIS FILE JUST YET.
I'd like to point out that the macro will work regardless what your scene looks like in terms of lights, camera position, etc.
I have not yet tested it with files containing more than a minifig, plus the minifig don't actually advance as they walk (be patient - it will come).
3. Open the L3P-generated file and comment out (or delete) the last object placement before the floor, background, camera or lights settings. If your ldraw file was called minifig.ldr, the line should look like the one bellow
object { minifif_dot_ldr #if (version >= 3.1) material #else texture #end { Color7 } }
To comment it out, add two dashes in front
//object { minifif_dot_ldr #if (version >= 3.1) material #else texture #end { Color7 } }
4. Inmediately after, add the line
#include "m_walk.inc"
(I've included samples of raw and modified L3P code at the bottom of the page)
5. Render your l3p generated scene - POV should spit out a sequence of files. For it to work properly, you must make sure that m_walk.inc is in your povray library paths (look in the POVray help file for help). And you must add the appropriate .ini or command-line parameters for animation (see below). In any event, it should always work if both m_walk.inc and m_walk.ini are in the same directory as the pov file to be rendered.
Advanced commands
6. The include is not capable of reading the colors of the L3P generated secene. So it will assign defaults one (yellow skin, black hips, gray everything else - skeletons are rendered all white). You can re-specify colors with the following parameters (type them into you file)
#declare M_L_Leg_Color=Color2 // Left leg color(as identified in the L3P code)
#declare M_R_Leg_Color=Color2 // Right leg color(as identified in the L3P code)
#declare M_R_Arm_Color=Color1 // Right arm(as identified in the L3P code)
#declare M_L_Arm_Color=Color1 // Left armcolor(as identified in the L3P code)
#declare M_Torso_Color=Color28 // Torso color(as identified in the L3P code)
#declare M_Hips_Color=Color0 // Hips color(as identified in the L3P code)
#declare M_Hat_Color=Color6 // Hat color(as identified in the L3P code)
7. You can also control the gait of the figure using 3 parameters
#declare L_Amplitude = 50; //Length of the arc made by the legs
#declare A_Amplitude = 20; //Length of the arc made by the arms
#declare H_Amplitude = 5; //Length of the arc made by the head (side to side)
(Notice how the animations at the top of the page move their limbs differently)
8. Finally, you can also control the pace of the animation by using different Final_Frame settings.
The basic m_walk.ini file is listed bellow.
Antialias=On
Antialias_Threshold=0.3
Antialias_Depth=3
Initial_Frame=1
Final_Frame=15
Initial_Clock=0
Final_Clock=1
Cyclic_Animation=on
Download example of altered code