Creating and Animating 3D Resource Trees in Blender

First Steps

If you don't use a mouse (like me), make sure to set your user preferences. Go to File > User Preferences and select 'Emulate 3 Button Mouse' and 'Emulate Numpad'.

Then, make sure you're viewing the model in Orthographic Mode. You can do this by pressing the numpad '5'.

Resource Tree Model

Assigning Materials (Colours)

Make sure you're in Edit Mode.

This will enable you to select a vertex, edge or face to set a material to.

Choose Face Select

In my case, I chose face select.

Outliner

Notice that your outliner (on the left) has set all objects to be visible. To make editing easier, I've set the visibility to one object at a time.

Set the visibility

Now that I've set visibility to the Big Leaf only, the rest of the objects are hidden. (Don't worry, you can turn on the visibility for them later.)

Face Selection

To get a close-up view, use Shift + B to zoom in and Alt + Left Click to move the camera. Then, right click on the face of the object that you want.

Note: To select multiple faces, press Shift + Right Click.

Assign Materials

Select the object you want to assign a material to/colour.

Select the 'Material' button.

Select +

Click New.

At the 'Diffuse' section (you might have to scroll down if you can't see it), click the colour and it will prompt you to select a colour.

It'd be a lot easier and quicker if you already know the colour (using hex/RGB code) you want to assign to your object. If not, you can always choose a colour from Blender's colour picker.

Notice that the colour is now assigned to the Big Leaf object. Now you can assign materials to other objects using the same technique.

Final Result

Animation

For resource trees, I've done four animations (grow, die, produce resource and harvested from using the same animation technique. I believe the 'Produce Resource' animation would be the most insightful - so read below to see how I did it!

Select Dope Sheet

The dope sheet allows you to set keyframes for each movement of the model.

Set the Pivot Point

Left click and place it as shown below.

Set the origin to 'Origin to 3D Cursor'.

The pivot point is now set.

Key Frame

Select the first (1) frame.

Scaling the food

The purpose of scaling the food is to demonstrate a 'pop out' animation (just like how fruits pop out from a tree in real life).

Press 'I' > LocRotScale.

Then, press 'S' to start the scaling. Move the cursor, then right-click to select the scale transformation position.

I've scaled it down until it shrunk.

Note: You can experiment with this by moving your cursor - then you'll notice that you can scale your object from small to large and vice versa.

Once you've set the position, press 'I' > LocRotScale again.

First Keyframe

Notice now that you have an active keyframe in your dope sheet. Then, you can add more keyframes as you go by following the same steps.

Converting the Caveman 3D Model to Sprites

The 3D model in Blender was converted into sprites using this step-by-step guide: Converting 3D Models to Sprites