This plugin fills in another gap in the Blender modelling experience. It
provides a means of setting up an unlimited amount of "background images",
or to be more precise "reference images". noThese planes can be
positioned/scaled/deformed to your liking and will seemingly appear behind
your transparently rendered geometry. In fact the reference planes are
transparent themselves and drawn on top of the geometry. This means it is
possible to use the planes for both sides of your geometry (front/back,
right/left, top/bottom), whatever way you look at them, they will always be
drawn transparently on top of the geometry.
Documentation
Go to User Preferences->Addons and enable the TranspRef addon in the 3D
View section. A TransRef pulldown will appear in the N panel (pull + icon on
right of 3D view). It will be empty until you select a standard
Mesh->Plane with four vertices. Click the file browser icon in the
N panel->Transpref section and load up an image, the image will be
projected over the scene contents, carefully filling the space bounded by
the selected plane, which you can afterwards translate, rotate, scale and
deform(editmode) to your wishes. When you select an image, also a
Transparency slider will appear, put it somewhere low so you can see your
geometry behind the reference planes.
Works well in perspective mode now too.
NOTE: the reference planes shouldnt occlude object selection, thats why you
can only select them by clicking the plane edges.
NOTE: you can create as many reference planes as needed. Reselecting a plane
later, enables you to access image path and transparency values.
HINT: you can use the reference planes from both sides. I recommend to model
in orthogonal mode (which is a good idea anyhow) if you want this to work
correctly.
BEWARE: reference state will be saved along with your blend file