# Blender 3D: Noob to Pro/Aligning Vertices with a Guide Image

|previous=Background Images
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Note: Some pictures are outdated.

This tutorial is about using guide images to place vertices in their
proper places in 3D space. The second tutorial is on how to take good
reference pictures. This tutorial assumes that you have completed all
previous tutorials.

This tutorial describes the use of the *background image* feature of
Blender to assist in creating models of 3D objects. The background image
provides a reference for the dimensions of the object, similar to the
way the floor plan and elevation views of a house provide dimension
information for the actual house. Guide images are not rendered, and may
be removed after the model is completed, or they may be retained as part
of the internal documentation of the model. Background images are not
generally useful for other \"image\" purposes such as materials,
textures, and actual background images in a scene, just as a floor plan
is not actually visible after a house is constructed.

## Background: orthographic projection

!orthographic projections in six
directions{width="300"}
**orthographic
projection** is a
technique used by architects and engineers to describe a
three-dimensional object by the use of several two-dimensional images,
or \"projections.\" In architecture, the projection as seen from above
is called the \"plan view\" or \"floor plan,\" the projection as seen
from the front is called the \"front elevation,\" and the projection as
seen from the right side is called the \"right elevation.\" Orthographic
projections are intended to assist builders in creating an actual 3D
object.

A Blender user also wants to create a 3D object, in this case a model.
Blender provides a way to use a set of one or more orthographic
projections as a guide for object creation. Because the images are
conceptually \"behind\" the object from the appropriate point of view,
Blender calls these 2D images *background images*.

Each background image is located \"at infinity\" in an orthographic
view, and there may be one image in each direction: back, front, top,
bottom, left, and right. we can use one or more background images to
assist our modeling effort.

For example, to model a house, we can put the \"floor plan\" on the
bottom, and build the house above it. We put the front elevation image
on the back background, and build the house in front of it. We put the
right elevation image on the left background, and build the house to the
right of it. The background images can be diagrams such as floor plans,
or they can be photographs of an object taken from sufficiently far away
to provide undistorted dimensional information.

Reasonably enough, an orthographic projection is only useful in Blender
when in orthographic mode. Blender enforces this to prevent you from
making mistakes: the orthographic image is only displayed in the
background when you are in the orthographic view mode.

## Making a Simple Pyramid

![](BlenderMakePyramid.png "BlenderMakePyramid.png"){width="300"} First
we are going to create a pyramid the easy way. Then we are going to show
how to use different viewpoints and images as a guide to place vertices
correctly in 3D space.

Get rid of the default cube. Press 
and select Mesh→Cone. Set the number of vertices to 4, and Set \"Capp
fill Type\" to \"Nothing\". Click OK. There's your pyramid.

**Note:** Do not render this looking up from the bottom, as it will
appear invisible, as the interior faces of models are ignored by most
rendering engines.

### Save the top vertex for later steps

Enter Edit mode (). First, unselect all
the vertices by pressing . Next, select
the bottom four vertices of the pyramid and delete them with
 or .
The only vertex left will be the vertex which makes the tip of the
pyramid. This will be used later.

## Using the guide images

Now that we have the pyramid the easy way, let\'s learn how to use guide
images as references to build models.

### Window Layout

![](Blender3d_view_name_setting_location.jpg "Blender3d_view_name_setting_location.jpg"){width="300"}

Split the Main 3D view window in to 4 windows (2 x 2).

:   **Reminder**: to split windows, move the mouse to the border of the
    view, when the cursor transforms into arrow, right-click and choose
    \"Split Area\". (Explained in the guide: Noob to Pro/Blender
    Windowing
    System.)

\
The point of view in each window are like this:

:   {\| border=1 width=\"30%\"

\|- align=center \|**NUM7**\|\|**NUM0** \|- align=center
\|**NUM1**\|\|**NUM3** \|}

And if you click on View, you can see that these windows are
respectively:

:   {\| border=1 width=\"30%\"

\|- align=center \| *Top* \|\| *User* \|- align=center \| *Front* \|\|
*Right* \|}

By knowing which view you are looking at you may find that you quickly
get the idea of what you are doing and can proceed somewhat intuitively
in this section on your own without following all of the step by step
instructions.

Note: The quick way to achieve this layout is to go into Quad-View
(CTRL-ALT-Q)

### Guide images

Now, we need some images. These come from a source outside of blender.
For this tutorial, we need a floor plan of our pyramid, a front
elevation view, and a side elevation view. The floor plan of our pyramid
is a square, and the front elevation view is a triangle, as is the side
elevation. We will cheat and use the same source image for both the
front and side elevation. We can make a picture of a white square and of
a white triangle in the GIMP, Paint :) , or some other image editor. Or
we can find appropriate images somewhere.

#### Method 1 download and use

!Save the triangle with a black
background
Download the black and white triangle image on the right of the screen
and use that. This image is, minus the checker pattern at the border,
198 x 198. (click it once to get the larger version, right click on the
larger one, and save)

#### Method 2 roll your own

!The square and triangle
relationship

You want to make a triangle, for the ground plane you don\'t need a
picture.

**Noob note** Make sure that the *drawing* of the square is *square* and
not just rectangular. Make the triangle the same width and height as the
square. Make sure the apex of the triangle is directly above the
midpoint of its baseline.

##### Specific instructions for Photoshop

Make a square selection of \"n by n\" size, remember the value of \"n\".
Fill it with white color and save. To create a triangle of needed
properties make a rectangular selection of same (n by n) size, on a new
layer, click **RMB** on your document, choose \"Transform selection\"
option in the pop-up menu. Once you are in \"Transform selection\" mode,
right-click the blank image again. This time the pop-up menu would be
different. Choose \"Perspective\" from it, and with **LMB** drag one of
the two top vertices toward the other. Once the vertices meet (in the
top-center of the image), exit the transformation mode, and fill the
resulting triangular selection with white.

Save the files to a place that is easy to access. Blender only supports
the TGA, PNG, and JPG image formats.

##### Specific instructions for Gimp

Turn on the grid (View-\>Show Grid, View-\>Snap to Grid), use the
rectangle select with a fixed aspect ratio of 1:1 (in the tool options
panel) to select a square that you can flood fill. For the triangle, use
the node tool to draw a triangular path, convert to selection
(Select-\>From Path) and fill it. Or you could just use Inkscape\...

Save the files to a place that is easy to access. Blender only supports
the TGA, PNG, and JPG image formats.

### Background Images

![](Importing_Image.jpg "Importing_Image.jpg"){width="300"} Load the
images (as described in the previous module) like this: In the 3D view,
make sure the Properties Shelf `<b>`{=html}(N)`</b>`{=html} is visible.
Look for the Background Images panel; it will most likely be collapsed,
so expand it. Initially it will have no background images to view. Check
the box at the top. Click the "Add Image" button once, and this will add
one entry to the list of background images. Then, with \'Image\'
selected, use the Open button to navigate to your image file.

Load the white triangle (the front elevation view): this places it
infinitely far \"behind\" the model. You can see the image in the front
view. Similarly, load the right elevation (coincidentally, you can see
the same triangle image in the right view window, to place it infinitely
far to the left.

If necessary, zoom out so that you can see the whole background image in
each view.

Now you have now placed your guide images for making your pyramid.

### Sides

![](Blender2.75a_make_vertices_background_image.jpg "Blender2.75a_make_vertices_background_image.jpg")
Make sure you\'re in Toggle Quad Mode. The vertex that is left will be
the topmost point of the pyramid. Use the **GKEY** to move the vertex
around. To get it in the right spot, line it up at the top most point in
the **front** and **right** windows. If you look in the **top** window
the vertex should appear to be in the center. Make sure to keep the
vertex highlighted for the next step.

\
Now you can begin to create individual vertices with **CTRL + LMB**. Be
sure you don\'t create vertices in the Top view cause that will confuse
you completely.

First line in the pyramid in front view then place a new edge between
the last made vertex and the top vertex by selecting them and hit \"F\".
Then do the right side, after selecting the top vertex, exactly the same
way. (Don\'t do the bottom side)

### Make Faces

![](Blender2.75a_make_faces_background_image.jpg "Blender2.75a_make_faces_background_image.jpg")

Select the side vertices of the corners were you want a Face and Tick
\"F\" Do this for every Face you want to make.

![](blender2.75a_make_faces_made_background_image.jpg "blender2.75a_make_faces_made_background_image.jpg")

![](blender2.75a_Pyramid_background_image.jpg "blender2.75a_Pyramid_background_image.jpg")

