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2: The "floor" on this scene goes on forever. You see common perspective attributes in this picture. But specifically there is the vanishing point. In the idea of a FOV, light is absorbed into a point, and 45 degrees from this points, faceing direction is where light would be absorbed. Lets try increaseing the feild of view to 90.
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3: Now that the FOV is 90, more light is being absorbed into the picture that you see. And the vanishing point has a more "wider" effect.
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4: Here I added two boxes so that you can see where the vanishing point is easier.
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5: Here I have the FOV set to 150. Things that are normally close to you seem farther away because more light is being absorbed from the edges of the screen, making what ever is in the middle seem smaller. But what if the FOV was infinit?
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6: Here is the FOV when it is set to infinit. This is called orthographic perspective. The concepts have changed now. There is no more vanishing point anymore. Instead of a point, it is now a surface. So instead of thinking of absorbing light into a point, your "eyes" are now a surface. A surface in geometric terms has an infinit amount of points onto it, so light is being absorbed according to where the surface is faceing. So instead of FOV angles, all light is aborbed parallel to the surface.
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7: Note how we are able to see 3 surfaces of the box at the same time. And how all parallel edges never cross each other unlike how in normal fov, when they all lead to a single vanishing point.
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8: And for the cylinder, we are able to see half of its round surface.
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9: But if we where to see the object from the top, we would be unable to see its sides. This is because the surface is perfectly parallel to the surface that we are using "see".
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10: And if we where to view it from the side, both the ground surface and the top and bottom of the cylinder are unviewable.
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11: I should also point out that as we look perpendicularly at the box's corners, all of the edges that lead outwards from it are being emitted evenly while the other outer corners are following the laws of rectangular objects that compliment that edge.
(opposite angles are equivillant)
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12: Thats it!
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Any object in the 3rd dimension can be put perfectly into a box. So this can be applied to irregular shapes if you can draw a bounding box over it to make sure the perspective is correct.
Quick makes to make sure it follows these laws.
And how all the edges that define height are EXACTLY the same.
