V-Ray Lesson 2

 Antialising-антиступенчатость and setting up your scene.
A bit of history: When drawing a line, vertical or horizontal is fine, however, once you go diagonal, then you get into the problem of correct pixel construction in terms of stairs.

To solve this problem, the renderer renders the picture normal 4x the size of the set picture and then shrinks it to the original set picture. When it shrinks, it combines the pixels together creating a blur effect. As a result, the stairs become blurred and the picture looks good. However, when the picture is increased 4x, then the process time takes 16 times longer.

Vray has 3 methods of antialising,
1) Fixed- the oldest (takes the picture increases and shrinks it, make the area bigger)
in v-ray:: fixed image sampler, subdivs - if 1, doesn't increase size. With 4 subdivs is the best quality, i.e. increases picture 4x. If in the picture you still have stairs due to light, then you have to reduce the intensity of the light. It is not a problem of antialising. To correct the problem go to color mapping in vray options and click two check boxes: subpixel mapping and clamp output.
Production quality size of render is 3508x2480 at 300dpi
2) Adaptive DMC - the most optimal, has similar function as fixed, only in this case it blurs only the needed parts not the entire picture.
In its options, you have min and max subdiv options. min means that if you don't need to blur, then use the min value, if there is a portion that needs to be blurred, vray will use use the value in max. It is twice as fast as the fixed.
3) Adaptive subdivision - the fastest good quality renderer, best to use for draft. In its options, setting the min and max rate to 0 and 3 will be comparable to the DMC options of 1 and 4.

So in summary, use antialising, subdivision for draft and for rendering, use DMC. The most important factor in rendering is the actual size of the picture, so the more pixels, the better the picture. For draft a good size is 1754x1240.

You can also use the antialising filter. Filter VrayLanczosFilter, makes the image slightly softer with a size 3. Used sometimes in nature mort. For interior, use either VraySincFilter, which makes all objects sharper with size 4. Makes a  photorealistic photo with a tripod and high exposure.

V-Ray Fur is similar to displacement, however fur gets better quality.
It can only be applied to a surface with a lot of polygons. The more polygons the better the fur rendering. 1x1 plane will kill your computer and you'll have to restart.
To use, example 1. Create a circle centered at 0 and 100 radius. Go to modifier and select garment maker.
In fur modification options, one of items to pay attention to is in the Distribution segment in the Per area. For exteriors, use 0.01. For interiors, use around 4, which makes it very dense.

Another example:

For rug, use Length of 2, Thickness of 0.2, Gravity of -1, Bend of 3 (which makes each fur curl up), Knots - 6 per area 2
For comforter, use length 6 or more, thickness of 0.2, gravity of -4 (so that the fur gets pulled down), bend of 1.5, knots 10, per area-3
To apply material to the fur, create a regular material in the diffuse area install a bitmap, with tiling of 2 and 2. Apply this material to the object and the fur object.
If you want to make an arc or other polygonal object and apply fur to it, apply modifier quadrify mesh which will break the object in further polygons.

Another example of grass creation. Instead of using fur, use displacemap.
To use grass you need a lot of memory, 2nd you need a specific bumpmap. Use a bump map i.e. grass displace and apply material to grass diffuse. Apply UVW Map to wall, size 200x200x200 (based on the side of the bitmap being applied) after that is done, apply another modifier vraydisplacementMod. If you use a plane to apply the dispacement, use the 2D mapping, if a more complex object, then 3D. In the textmap apply the difuse map. Then apply amount around 6. In 3D mapping options, increase the quality (the lower the better quality), place around 2 (good quality), 1 is ideal. Also, set the checkbox of Keep continuity, it keeps the edges stitched together. For grass, set amount to 8, under 2D mapping, Resolution is the detail of map, set it to 1500, Precision is the precision of putting the map where it should be, set it to 15. There is a plug to create grass called Grass-o-matic. The result of render is as follows: