Spot is another perception content of Miarmy. It's actually a (position) point in 3d space.
With spot channelssentences, agents can test distances and directions with the spots and interactive with them, such like follow a spot, or trigger some behaviors near a spot.
Additionally, spot support indexing.
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Note: you may notice there are some extra attributes on each spot, they are actually belongs to build-in force field, we designed spot with a build-in force field combo due to that in many case we need them both working together.
We will talk about this later in Part 7: Physical Simulation – build-in force field (Combo (Spot and Field))
(left) Spot and build-in force field combo, (right:)build-in force field attributes(Left) spots in scene, (right) spot attributes
You can create spot in Miarmy > Perception Contents > Create spot, and each spot has 1 spot related attribute or by shelf button 
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The spot .x channel is on LEFT(RIGHT) sentences will return the angle between the Z-axis of agent and the line of agent to the spots (angle between black line and green lines, shown as below). And then use these result determine agent at left or right.
In the following example, the spot .x channel is on LEFT(RIGHT) sentence will return α degree for spot A, β degree for spot B and γ degree for spot C, so the input results should be [α, β, γ], approximate [45, 130, -70], (LEFT, LEFT, RIGHT)
The spot .x test is on LEFT(RIGHT) test spots in horizontal space whereas the spot .y channel test is on UP(DOWN) sentence tests spots in vertical space.
spot .x channel is on LEFT(RIGHT) sentences example
The spot .d channel to me distance sentence will return distances between the agent and the spot in 3d space, like the following picture, the spot.d channel will return the input results [d1, d2, d3] from current agent.
spot.d channel spot to me distance channel example