Changing the texture of a part of a terrain

[sinapse]

Hey guys, here is my exact problem: I want to put a grass texture to show that for example this area is a park or a green field, what I have is a polygon which indicates that this area is needed to be a green field. So I tried adding grass meshes like tutorial 5 of intermediate tutorials but that sure resulted in an ugly issue of performance as there are so many meshes which should be rendered just for an small field of grass! So I thought maybe I need to just put a texture on the ground. I started to create a manual (triangle fan) to create a surface for that polygon and load the grass texture on it which resulted in the following image. As you can see because I didn't add any clue about the height between points, the grass surface intersected the terrain mesh. I did implement an easy way and didn't further my thoughts but here is my question: am I doing the right thing? I mean isn't there any embedded solution in the terrain manager for this that I am not familiar? If not, what solution do you recommend me to do this?

[frostbyte]

you can blend up to ( i think ) 6 layer of textures with difuse and normal and get something similiar to grass with no animation and only on ground surface
if you want higher stuff like flowers, bushes and stuff- you can use mesh-instancing or better yet static-geometry( i assume you are using ogre 1.x )
there is also a plugin called pagedGeometry with optimized rendering techniqe( 2d billboards-mesh imposters, paging and lod levels ) just for grass...

lastly...all i learned on terrain and grass is from Ogitor source code{ terrrainEditor( with texture blending )+grassEditor(pagedGeometry ) };
since its the best example of a working-bugfree terrain-managment/editing, i advice you to download it and take a look at the code...

[loath]

there are a family of functions like Ogre::Terrain::getHeightAtTerrainPosition() that you can use to get the height at a position for the grass or meshes.

+1 on everything frostbyte says.

[sinapse]

@frostbyte
Ok, I was not familiar with blending in terrains. Now that you mentioned it I feel like being in the right path thank you!