Is there an easier way to draw a shape in 3d to match X,Y, Z of photo?

Question

I usually start a project in 2d and import photos, draw shapes and text in this 2d environment. I find it easier this way because they all start out on the same plane, and when manipulating in 3d later, this initial plane acts as a reference plane that I can shift X,Y,Z and rotation paramaters from. I then add a new camera and turn everything into 3d. However, as I work further in the timeline, I sometimes want to add a rectangle that overlaps exactly on top of a photo lying in 3d space as to cover it. When I start the shape command in the active camera view and draw the rectangle to match the outline of the photo, it seems like the photo and rectangle are on the same plane in this view. However, when I check this by going to the perspective view and checking from other angles I see that the rectangle was placed on an arbitrary plane and the rectangle is not overlapping the photo.
To correct this, I open the inspector of the photo and write down it's X,Y,Z positions and also it's X,Y,Z rotation parameters. Then I go to the rectangle that I have already drawn and in the wrong plane, open it's inspector properties, and replace with the X,Y,Z and rotation parameters of the photos. Then fine tune the orthogonal positions and scaling within the plane with the 3d tranform tool. This seems like a lot of work, especially when I have to do it a 100 times. Looking for an easier way to draw a shape on the same plane of a photo in 3d space.
Thanks

Answer 1

Howdy,
This is a really good question about one of the bigger challenges of building a 3D project. When you add objects to the Canvas (including drawing), they get added in the camera's viewspace, facing the camera and sharing the same up-vector (i.e. positive Y is up). This is all well and good, but what about doing what you ask, where you want to add an object in the localspace of another object? Let's look at your example: adding a shape that is coplanar to a photo, with the camera not necessarily aligned with the photo.
As Mark suggested, you can draw the shape in the camera's viewspace and then drag-and-drop the Position and Rotation channels from the photo onto the shape. This will replace the shape's Position and Rotation values with that of the photo, making them coplanar and located in the same place. The shortcoming of this method is that you draw the shape at a size that seems correct in the Canvas, but once it's moved to the same place as the photo, it will often turn out to be too small or large. Then you have to make further tweaks.
Another solution is to use the Isolate command. Isolate temporarily aligns the current view to the selected object and solos that object. So you could isolate the photo and then draw the shape in the Canvas and it will be coplanar with the photo. The only caveat is that the moment you finish drawing the shape, it will disappear. This is because the photo is still isolated (and soloed). As soon as you de-isolate the photo, everything will reappear.
The easiest way to use Isolate for new photos—not ones already in the project—is to place the photo in a 3D group, position the group where you want the photo and shape to be, then isolate the group and add anything you want to it (shapes, image, text, etc).