Linear gradient in Texture2d run-time

Good afternoon!

I genrerate (setPixel) Texture2D (100, 100). I want to draw on triangle gradient texture with known coordinates v1, v2, v3 - corners and corners colors color1, color2, color3. Sample - a white texture with a linear triangle gradient (v2 - Green; v1, v3 - Red):




Nobody will tell the script for such a thing?

 

Have you considered skipping textures all together and just using vertex coloring?

 

And here is how to make 'a white texture with a linear triangle gradient'

Code (CSharp):

1.     Texture2D tex;
2.     Renderer rend;
3.     // Use this for initialization
4.     void Start () {
5.         rend = GetComponent<Renderer>();
6.         tex = new Texture2D( width, height );
7.     }
8.  
9.  
10.  
11.     //Texture size
12.     public int width, height;
13.     //x and y coordinates of 3 vertex positions (in texture space 0->width)
14.     public int v1x, v1y, v2x, v2y, v3x, v3y;
15.     //Corner colors
16.     public Color color1, color2, color3;
17.  
18.     void Update () {
19.         for (int x = 0; x < width; x++) {
20.             for (int y = 0; y < height; y++) {
21.  
22.                 tex.SetPixel( x, y, PointColor( x, y ) );
23.  
24.             }
25.         }
26.         tex.Apply();
27.         rend.material.mainTexture = tex;
28.     }
29.  
30.     Color PointColor ( int x, int y ) {
31.         //Calculate barycentric co-efficients a,b,c
32.         float d = (v2y - v3y) * (v1x - v3x) + (v3x - v2x) * (v1y - v3y);
33.         float a = ((v2y - v3y) * (x - v3x) + (v3x - v2x) * (y - v3y)) / d;
34.         float b = ((v3y - v1y) * (x - v3x) + (v1x - v3x) * (y - v3y)) / d;
35.         float c = 1 - a - b;
36.         if (0 <= a && a <= 1 && 0 <= b && b <= 1 && 0 <= c && c <= 1) {
37.             return color1 * a + color2 * b + color3 * c;
38.         } else {
39.             return Color.white;
40.  
41.         }
42.     }

 

Thanks it works for 1 triangle, but if I need to be on the texture draw N triangles. That would not want to run through the loop the entire length of the texture.

 

if you use the vertex color, is it possible to add noise to the texture blending mode for mesh?

 

You can use the vertex colors to tint a bitmap (eg. noise) that is applied in the normal fashion