[vertex shader]
void main(out float tex : texcoord, inout float4 pos : sv_position)
{
    tex = pos.x;
}

[pixel shader]
float4 main(float tex : texcoord) : sv_target
{
    int i;
    float x = 0.0;
    for (i = 0; i < 10; i++)
    {
        x += i;
        if (tex > 0.5 && i == 5)
            break;
        if (tex > -0.5 && i >= 7)
            continue;
        x -= 1;
    }
    return float4(i, x, 0.0, 0.0);
}

[test]
todo draw quad
probe (  0, 0, 159, 480) rgba (10.0, 35.0, 0.0, 0.0)
probe (161, 0, 479, 480) rgba (10.0, 38.0, 0.0, 0.0)
probe (481, 0, 640, 480) rgba ( 5.0, 10.0, 0.0, 0.0)