Camera Controls in Blocks

All of the camera controls described in this tutorial are available in Blocks, under Webcam Controls. A few Blocks-specific details are worth knowing.

Setter Blocks

The setter Blocks under Webcam Controls can change/toggle, when choosing “use return value” or “ignore return value” from each Block’s context (right-click) menu.

Blocks Setters — Examples of Setter Blocks with togglable return values

In either form, the setting task is performed.

The “non-return” version comment is:

Set the gain. Right-click, “use return value” for a Boolean indicating success or completion.

The “plug” version comment is:

Set the gain, and return a Boolean indicating success or completion. Or right-click, “ignore return value”.

Shared Blocks

FTC Blocks offers an arrangement where 3 similar Blocks use a pull-down list to share a common structure (and common comment):

Blocks Exposure — Examples of Exposure Blocks with pull-down lists

This is used six places in the Webcam Controls section.

Pan-Tilt Holder

See this Block with the NEW operator (green oval):

It’s not needed if the OpMode will call getPanTilt() and assign it to the variable, as shown above (yellow arrow).

It is needed if instead the OpMode will next try to get (or set) that variable’s pan and/or tilt values, or try to pass that variable to setPanTiltHolder(). The values will be zero.