# T2.2 Draw triangles with vertex colours using shaders

## Github code

{% embed url="<https://github.com/zhaoyoubing/proj02/releases/tag/tag_c_vertex_colour>" %}

<figure><img src="https://3464970502-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F3JUKGJZ67JX02QZdPhsy%2Fuploads%2FSXK6Vwy38hoUBCYSWPHZ%2F65e84395-1289-48f0-bbd7-52aeb8a0ea75.png?alt=media&#x26;token=335ca99f-feb3-487c-845d-c2ccddaecece" alt=""><figcaption></figcaption></figure>

Taking the X axis as Red and the Y axis as green, we can assign RGB values to each vertex

```cpp
    // vertex data with RGB colour components
    GLfloat verts[] = {
        -1.0f, 1.0f,  0.0f, // v0
        0.0f, 1.0f,  0.0f,  // v0 colour green
        -1.0f, -1.0f, 0.0f, // v1
        0.0f, 0.0f, 0.0f,   // v1 colour black
        1.0f, -1.0f,  0.0f, // v2
        1.0f, 0.0f,  0.0f,  // v2 colour red
        1.0f, 1.0f,   0.0f, // v3
        1.0f, 1.0f,   0.0f, // v3 colour yellow
    };
```

## What we get

<figure><img src="https://3464970502-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F3JUKGJZ67JX02QZdPhsy%2Fuploads%2FY1cSefdBoZC5X2XKOilB%2Fimage.png?alt=media&#x26;token=ab383f49-e50e-42b3-9486-877dc4a905b6" alt=""><figcaption></figcaption></figure>