Executing Func over a specific domain in generator

Question

I have this example generator that fills a region (0,0,100,100) with black:

class MyGen : public Generator<MyGen>
{
public:
    Var x, y;
    Output<Func> output { "output", Int(32), 2 };

    void generate()
    {
        output(x, y) = x + y;
        RDom dom = RDom(0, 100, 0, 100);
        output(dom.x, dom.y) = 0;
    }

    void schedule()
    {
    }
};

The region is filled correctly, but because of the pure definition, the rest of the image is a gradient (x+y).

Is there a way to write a pure definition that's not going to be executed (e.g. output(x,y) = output(x,y))?

Can I execute a Func over a specific domain (e.g. Input<int>s that define the region) without impacting the rest of the image?

score 2 · Accepted Answer · answered May 04 '17 at 14:59

2

Here's how you write an unexecuted pure definition:

output(x, y) = undef<int>();

It's a bit dangerous though for anything other than outputs, because Halide doesn't statically check for use-of-undefined values. valgrind is your friend.

answered May 04 '17 at 14:59

Andrew Adams

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Executing Func over a specific domain in generator

1 Answers1