Sprites

[leonora]

hi,

If I have a script that creates many many spheres, and I want to speed up the whole process by using sprites (i understand this is a texture applied to a poly-surface) - what exactly do i do?

i mean what do I replace the "sphere;" command with?
Do I need to create a surface? But how can you have a surface without an object?

sorry, im a bit confused :S

[gwelch]

I am not sure that this will help you with your script because there are many set up steps needed for partilce sprties to work.

A sprite is a particle type one can choose after creating a particle, other types include. sphere, blobby, multistreak... The sprite particle type displays flat planes that always faces the camera. The idea is to map a texture (often with an alpha channel) to the sprite planes. The texture can be displayed many ways on the sprite including animated, a randomly assigned texture from a series of files or a single texture file repeated on every sprite. The numbering of the texture files for an animated sprite need to be without frame padding to work. Saving the animated files with Fcheck is a quick way to insure the numbering will work. There is a sprite wizard under the particle menu that can set the sprite texture options. A limitation of sprites is that they can only be rendered with the hardware render. A workaround that allows a software render of a "sprite" is to instance a flat geometry plane (Poly, nurbs,..) to the partilce and that plane will software render. The trick is to make the instance always face the camera by connecting the instanced planes rotation to the camera rotation. For animated software sprite textures, one would use an animated texture on a material, and for random textures one can create many planes all connected to the camera's rotation and then randomly assign textures to the planes and randomly instance the planes to the particle instancer.

[naughty]

QUOTE(tar valon @ 03/14/06, 02:52 PM) [snapback]231096[/snapback]
If I have a script that creates many many spheres, and I want to speed up the whole process by using sprites (i understand this is a texture applied to a poly-surface) - what exactly do i do?

I did a similar thing ages ago (before I even knew what particles were in Maya) and what I did was pretty straight forward. here is my process in psudo-code:

CODE
get selected objects;
loop through each object
{
   get/STORE it's pivot position;
   create a new polyPlane;
   move polyPlane to the STOREd position;
   connectAttr it's rotations to the camera;
   apply the shader with your texture on it;
   delete/hide your original object;
}

if you know any MEL this is all very simple and doesn't use particles. However, particles may be even better and easier for this, but I've never used them for sprites so I can't comment..

[edit]
In fact, I've just found this screenshot of my old sprite creator UI..! Sprite Creator
[/edit]

:nathaN