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This tutorial describes how to duplicate and chaotically locate some objects (meshes) on the surface using particles. This method is useful for creation of textures, for example: leaves' texture, macadam's texture, any other objects that are on the surface.
We recommend you to take into account not only our advices, but the possibilities of your computer. Afterwards, the created file can serve as a generator of textures (you may replace models by new ones).
1. Create scene with good lighting, orientating on the power of your computer. Also it is advisable to activate Ambient Occlusion, the shadows should be rather soft. In our example only two lamps were used: Area – for shadows and Lamp – for lighting. Locate camera on Z axis so that it is directed downwards and activate «Orthographic» mode.
2. Let's add a cube and make deflector out of it. For this you should delete one upper face and check Normals direction, the normals should be directed inside the object. Then activate options: Field and Deflection ( >> Objects F7 >> Physics >> Panels: Field and Deflection). As a result, we've got a trap for our particles (fig.1). This trap should be transparent. The easiest way to make it is to press button «Wire» in the Material buttons (F5).
3. Create colored or textured mesh-object for the future texture. In this example we use a simple arrow, but you may create everything you want: a leaf, a stone and so on.
4. Add emitter. It can be any mesh-object, in our case it is a plane, approximately 8 times smaller than the size of our deflector (fig.2). It is important to locate emitter and deflector in one single layer, otherwise the particles will go through the deflector during animation.
The normals of the plane (emitter) shoud be directed into our trap (deflector). Activate particles for the emitter. Attention, don't activate button «Static» (fig.3).
Select the mesh-object (arrow), then select emitter and make parent (Ctrl+P). Don't deselect the objects, now go to the «AnimSettings» panel and activate the «DupliVerts» button. Press «Alt+A» in 3d View to see animation, you'll see flying mesh-objects (arrows) instead of particles. You may change the amount of generated arrows changing values in the «Amount» option, that is situated on the «Particles» panel. After each change it is necessary to press button «RecalcAll» to have all data recalculated. Unfortunately the arrows are unidirectional at this stage. For elimination of this lack it is necessary to add several emitters and change the size and orientation of arrows that are assigned to the emitters. In this example we have 4 emitters, but the greater amount also can be used, usually 4-8 emitters. The easiest way to add emitters is to duplicate the first created emitter.
5. Check the quality of created animation (Alt+Ahift+A) and select any appropriate frame. For example 187 (fig.4). Here, in this frame you may tune the size and location of the arrows (if it is necessary). Check other parameters, colors and then render your created scene.