History: MOGRE GeneratingAGrid

            Sometimes its useful to have a 3D grid placed on the XZ plane as base of reference for your scene. This short code would show you how to construct the 3D grid using a ((ManualObject)) centered at the origin.

{CODE(wrap="1", colors="c#")}private void CreateGrid(int numcols, int numrows, float unitsize)
{
    ManualObject grid = mSceneMgr.CreateManualObject("grid");            

    grid.Begin("BaseWhiteNoLighting", RenderOperation.OperationTypes.OT_LINE_LIST);
    
    float width = (float)numcols * unitsize;
    float depth = (float)numrows * unitsize;
    Vector3 center = new Vector3(-width / 2.0f, 0, -depth / 2.0f);

    for (int i = 0; i < numrows; ++i)
    {
        Vector3 s, e;
        s.x = 0.0f;
        s.z = i * unitsize;
        s.y = 0.0f;

        e.x = width;
        e.z = i * unitsize;
        e.y = 0.0f;

        grid.Position(s + center);
        grid.Position(e + center);
    }
    grid.Position(new Vector3(0.0f, 0.0f, numrows * unitsize) + center);
    grid.Position(new Vector3(width, 0.0f, numrows * unitsize) + center);

    for (int i = 0; i < numcols; ++i)
    {
        Vector3 s, e;
        s.x = i * unitsize;
        s.z = depth;
        s.y = 0.0f;

        e.x = i * unitsize;
        e.z = 0.0f;
        e.y = 0.0f;

        grid.Position(s + center);
        grid.Position(e + center);
    }
    grid.Position(new Vector3(numcols * unitsize, 0.0f, 0.0f) + center);
    grid.Position(new Vector3(numcols * unitsize, 0.0f, depth) + center);
    grid.End();

    mSceneMgr.RootSceneNode.AttachObject(grid);
}{CODE}

The grid resolution depends on the parameter numrows and numcols. The unitsize parameter tells how big each cell is in world units.

This also constructs the grid with the predefined / hard coded "BaseWhiteNoLighting" material.

{img src="img/wiki_up/Grid.png" alt="Grid.png"}