Here’s a basic Tutorial using the Flatshot/STSC_Projective2D commands:
I’d like to paint a logo on a field that is 25 meters in front of a camera. The camera sit 15 meters above the field plane. The image should represent a sign 3 meters tall, 4 Meters wide. The sign will have some generic logo, of which I have Vector artwork.
In AutoCAD, I create the Camera with a position of 0, -25, 15. The Target is set to 0, 0, 0.
I create a 3DSolid Box, -2, 0, 0 by 2 , 0.1, 0 with a height of 3. I will need reference geometry in the form of a rectangle on the ground plane so I create another box, -2, 0, 0 by 2, -3, 0 with a height of -0.1. (This, and all resultant evidence of this reference geometry will eventually be discarded)
With a view from the Camera, I call Flatshot – and position the results to the side of the 3d geometry. Flatshot inserts it’s geometry as a Block Reference, so I explode that back to standard lines.
For the sake of better visibility, I go back to the standard Top view. Further to the side, I create a Rectangle that is 4 x 3. I position the logo into this “Square Rectangle” as I’d like it to appear.
I start the Projective2D command, make sure the initial setting is “From Ortho”, snap to lower left of the “Square Rectangle”, then upper right. I select the logo, then I select, counter clockwise from lower left, the four corners of the Flatshot generated lines that represent the Sign. The logo geometry should now match slight perspective of the Flatshot.
I call the Projective2d command again, this time switching the initial parameter to “To Ortho”, select lower left of the 3d reference box, then upper right, Select all the logo geometry that has the slight perspective, Then, counter-clockwise from lower left, select the corners of the Flatshot’s reference geometry. (Note: snap to the corners representing the top surface).
The result of that second call should recreate the proper logo when seen from the Camera.
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May your cursor always snap to the location intended.