I am pretty new Direct3D and have been looking for a solution to my problem for a couple of days. Most of the tutorials I have seen that cover textures only use one texture. For my program I have multiple textures that map to a specific collection of vertices that make up my mesh.
My question is how do I load multiple textures into my scene? and how do I map a collection of vertices to only one texture?
For example if I had a mesh of a car and I had a collection of textures like:
Tyres.dds
Body.dds
Cabin.dds
Given the car, how do I map the vertices that make up the tyre to the tyres.dds texture, body to body.dds and cabin to cabin.dds. All these textures have to render not just one.
Any help would be greatly appreciated,
Thank You
Usually this is done via submeshes. That means that the mesh consists of several parts that are represented as e.g. triangle lists. Each submesh is assigned a material. This material can be defined as you need. It may include diffuse color, roughness and the texture.
So when rendering the mesh, you would basically iterate every submesh, send the material parameters to the graphics card and then draw it.
Another possible solution in DirectX 10 would be to extend the vertex declaration by a TextureIndex variable. Or you could use 3d texture coordinates. This way, you can send all textures as a texture array to the graphics card and draw the mesh with one draw call. However, texture arrays are not suppported in DirectX 9. So you can either stick to method 1 or try to emulate a texture array.
Related
So as you see in the picture, i made a texture repeat on a rectangle(its size is 40,10,60) but it repeat the same amount of time on every face,so depending of the size of the face the texture is stretched.
In the picture you see that on the top face the texture repeat correctly and keep its original size but on the other faces it is streched.
Is there a way to repeat the texture without changing its size ?
Thank you for your responses.
screen of the problem
Edit : this script in c# does exactly what i want but is there a way to do it without a script since it was done in 2017 ?
https://github.com/Dsphar/Cube_Texture_Auto_Repeat_Unity/blob/master/ReCalcCubeTexture.cs
Unfortunately you will probably need to create a new material with the same image for each different scale using the 'Tiling' attribute:
*** Edit #1
The x and y Tiling values need to proportional to the scale of the plane or it will stretch.
If the size of the mesh being textured is static, you can change its UVs in a 3d program. You could even change the UVs via script.
Another option would be to look into worldspace (triplanar) shaders. These texture based on world position rather than the vertices local position.
If you are using Shader Graph, look at the triplanar node.
https://docs.unity3d.com/Packages/com.unity.shadergraph#6.9/manual/Triplanar-Node.html
I have a procedurally generated cube that has a hole(s) in it. The script will take a mesh (the white squares in image 1) and creates the shown holes based on the position of the squares (image 2) (in other words, the squares are pretty much randomly placed.) The problem I'm having is that the light on the mesh is completely messed up (image 3). Currently the Array of UVs for the mesh is an empty Vector2 array. I believe that the UV array the problem so then how can I get the list of UVs when the only information I can get on the mesh is the list of vertices and the list of triangles? Or if it's not a problem with the UVs, how can I fix this?
(In Unity C#)
If the problem has to do with the normals try:
mesh.RecalculateNormals();
Unless lighting is baked into the texture, it is more likely a problem with normals. You need to be more specific, show your shader code or how you generate vertices etc.
I am creating realtime scene in XNA, it is 2D using sprites only (rendered on quads, standard spritebatch with alpha map on sprites). I would like to create create simply lens flare, actually only occlusion around light source (I don´t need direction to center of camera to offset multiple sprites for lens flare, etc.) Only thing I basically need is to calculate how many pixels from light source sprite (small star) are rendered and according to it set scale of lens flare sprite (so scale 0 if sprite there are not visible pixels from relevant sprite).
I know how to do it in 3D, I read through this and tested few things:
http://my.safaribooksonline.com/book/programming/game-programming/9781849691987/1dot-applying-special-effects/id286698039
I would like to ask what is best and cheapest way to do it in 2D scene (counting how many pixels of sprite were rendered / occluded with per pixel precision or something comparable).
I know also stencil buffer could help but I am not sure how to applicate in this case.
Okay, two ways how to solve it, either kinda old school approach, using stencil to calculate count of occluded pixels and scale sprites of lens flare according to it.
Other way: modern approach, use screen space lens flare, isolate bright pixels (I recommend HDR rendering pipeline and use values of brightness above 1.0 to generate lens flares, but it depends on scene average and maximum) and generate ghosts, like so:
https://www.youtube.com/watch?v=_A0nKfzbs80&list=UUywPlxpmCZtuqOs6_bZEG9A
I'm trying to create tiled terrain in 3D with XNA. I checked tutorials on how to doit(Riemers and Allens). Allens tutorial has an exact result I want to achieve, however I'm not sure about performance - it seems he is using single quadrilateral to draw all terrain and process it with pixel shader, it means - whole terrain will be processed each frame.
Currently I'm drawing a quadrilateral for each tile(Example) - it allows to draw visible tiles only, but it also means that much more verticies need to be processed in each frame and a lot of "DrawIndexedPrimitives" is called.
Am I doing it right or Allens way is faster? Is there a way to do tiled terrain better?
Thanks.
Totally depends on your terrain complexity and size. Typically, you will have terrain tiles with more than one quad/tile (for instance, a tile could consist of 4096 triangles) and then displace the vertices to get the terrain you want. Still, each tile will be a indexed primitive, but a single draw call will result in lots of triangles and a larger part of the terrain. Taking this idea further, you can make the tiles in the distance larger so you don't get too much detail (look for quad-tree/clipmap based terrain approaches; you'll get something like this: http://twitpic.com/89y5kn.)
Alternatively, if you can displace in the vertex shader, you can use instancing to further reduce the amount of draw calls. Per-instance, you pass the UV coordinates into your heighfield and the world-space position and then you again render high-resolution tiles, but now you may wind up with a single draw call for the whole terrain.
For a small game, you might want to generate only a few high-resolution tiles (65k triangles or so) and then frustum-cull them. That gives you a large terrain easily and is still manageable; but this definitely doesn't scale too well :) Depends on your needs.
For the texture tiles, you can also use a low-resolution index texture and do the lookup into an atlas per-pixel or just store the indices in the vertex buffer and interpolate them (this is very common: Store 4 weights per vertex and use it to look up into four different textures.)
I've been producing this 2d tile-based game engine to be used in several projects.
I have a class called "ScreenObject" which is mainly composed of a
Dictionary<Point, Tile>
The Point key is to show where to render the Tile on the screen, and the Tile contains one or more textures to be drawn at that point. This ScreenObject is where the tiles will be modified, deleted, added, etc..
My original method of drawing the tiles in the testing I've done was to iterate through the ScreenObject and draw each quad at each location separately. From what I've read, this is a massive waste of resources. It wasn't horribly slow in the testing, but after I've completed the animation classes and effect classes, I'm sure it would be extremely slow.
And one last thing, if you wouldn't mind..
As I said before, the Tile class can contain multiple textures to be drawn at the Point location on the screen.
I recognize possibly two options for me here. Either add a quad at that location for each texture to be drawn, or, somehow.. use a multiple texture for the same quad (if it's possible). Even if each tile contained one texture only, that would be 64 quads to be drawn on the screen. Most of the tiles will contain 2-5 textures, so the number of total quads would increase dramatically with this method. Would it be feasible to add a quad for each new texture, or am I ignoring a better way to do this?
I'd suspect using a Dictionary would be slower than just using a straight array. If your world consists of 512x512 tiles then you allocate an array 512x512 (262144) in length. YTou can get any given tile in that array by using "array[x + (y * 512)]".
You know how many tiles there are so store an array where each either points to the tile at that position or has an index to the tile in a list (you will likely save memory this way as you can probably keep all your tiles in an array less than 65536, or maybe even 256, in size and thus store the index as a 16-bit.
You then find the area of your array you want to render. To do this optimally you want to avoid switching textures as much as possible. So first thing I'd check to see how big your tiles are I'd then try and combine as many of the texture into 1 big texture. Then set your UVs to sample a sub portion of this large texture. This way you should be able to limit the number of textures in use with a few big textures. Of course you will probably find that a given tile set (lets say rocky ground, for example) will use the same groups of textures. There may also be some blending across to grass somewhere so it may well be worth holding the grass textures in BOTH big texture to avoid doing so many texture swaps. ie sacrifice video memory for speed.
You then iterate over the visible portion of the array and draw all the tiles using texture 1 and then all tiles using texture 2 and so on.
I would recommend to use single VAO object composed from triangles + indices. Calculate position on client side and just update it on each frame (streaming).
Use texture atlas to store everything in single texture (to avoid switching states). You can use texture packer tool.
Render in one shot (if you have depth buffer enabled). Otherwise render first objects that opaque and then render everything that should be blended.