Making simple level with Blender

In this section we will have short but powerful introduction to Blender. We will cover just enough of model creation basics, you will need to create most of simple projects.

No, we will not cover animation, shaders or modificators here, but just enough minimum to create this ramp floor for our tutorial:

Wanted result

You will find lot of keyboard shortcuts here. And this is one of the most awesome features of Blender - you can work without menus or panels! Everything you need can be done with keyboard!

So let’s dive in Blender now!

Welcome to Belnder

When you open Blender, you will see some pretty image, made with Belnder, version information, some useful links and recent files

Blender

To close this window, simply click outside it. You will then see your workspace with the Default window layout (we will learn about them later). Workspace contains a few kickstarting items:

  • camera
  • light
  • cube

Workspace

You may be confused of the last one, but you will see shortly that so many cool things could be done starting with plain cube and modifying it. Oh, and about modifying: let’s switch to the Edit mode, hitting the Tab key:

Edit mode

You can exit it hitting Tab again. In the edit mode you can manipulate mesh’ edges, vertices or faces. To switch between these, use three buttons on the screen’s bottom:

Switching between edges, faces and vertices in edit mode

Let’s choose the faces editing mode. Unlike other 3D editors, in Blender selection is done with the Right mouse button. Select one face of the cube:

Selecting items in blender

You may have noticed that the axis arrows have moved in the selected face’s place. These are used to manipulate selected elements. Also, they show the orientation of the selected element. You can move the selected element by simply dragging one of the arrows. Selected element will be moved along the selected axis only:

Moving selected elements

The same operation, movement, could be performed hitting the G key. You can move other elements, too - this will change the form of our cube:

Moving edges

Now let’s try something more complex. See the Tools panel on your left?

Tools panel

Select a face in a face editing mode and click Extrude (or hit the E key). Your face will be extruded and you will be able to move it freely. But usually, designers move elements along some axis - this makes models more accurate. To fix the movement axis, just hit its letter while being in the extruding mode - X, Y or Z:

Extruding faces

Interesting fact: you may extrude both vertices and edges too.

Now, let’s use even more advanced operation, which is oftenly described later in tutorials on 3D modelling. Choose the Loop cut and slice operation from the Tools panel - you will see nothing. Until you move your cursor over your model. Depending on the edge, cursor is closer to, you will see purple rectangle, looping through your model:

Loop cut

When you click the Left mouse button, you will move to the next part of this operation - slicing. Just place the new edges where you want:

Slicing the loop cut

Now let’s create walls for our “ramp”. Create a few loop cuts alongside the ramp and we will start extruding:

Extruding one wall

Or maybe just moving faces?..

Moving vs extruding

No, that’s definitely not what we want! We want walls, not a new ramp! Hmmm… But if we will extrude walls one-by-one, it will be inaccurate… Hold the Shift key and right-click the two neighbour walls:

Multiple selection

Now we will work with three elements in the same way. Hit the E key and then - Z and extrude all three walls at the same time up:

Simultaneous extrusion

Now we need two more walls to prevent our hero (the ball, if you recall from the previous part) from falling aside. Select two edges at the corner of our ramp and hit the W key. You will see the context menu like this:

Editing context menu

Click the Subdivide item, and the selected edges will be connected right in the middle:

Subdivision for two edges

You can perform that operation on faces - that is oftenly handy. Now, if you undo your changes with usual Ctrl+Z (or Command+Z on Mac) and try to perform the same operation on four opposite edges, you will see there is a redundant (in our case) edge:

4-th subdivision

You can remove it by selecting that edge, hitting X and selecting Dissolve edges. If you choose the Delete edge - you will loose the neighbour faces, which were made of that edge.

Delete or dissolve?

So in the end we need to have two edges on the same line:

The needed edges

Now, switch to the Ortho View, choosing one from the View menu at the bottom of the screen, or hitting the Num 5 key:

View menu

Your workspace now should look different:

Ortho view

Using the View menu, you may switch between different views, perpendicular to your model.

Top view

Right view

Switching between different views will not clear the selection. And this is awesome! So if you try to move the selected edges in the Right Ortho View, you will move both of them:

Selection persistence

Yeeks… They move just along the Y axis, but not along the edge. But Blender easily handles that - you need to switch between coordinate system using the corresponding menu at the bottom of your screen:

Coordinate system

Use the Normal one and you will see the arrows at the selected edges changed:

Normal coordinate system

Now movement is done along the edge, just as we need:

Moving with Normal coordinate system

Try moving (yes, moving, not extruding) our edges up - they will move along the normal:

Moving edges in Right Ortho view

But if you click the mouse wheel and rotate camera, or even if you switch to the Top Ortho view, you will notice that our walls have different width:

Whoops...

So we need to make one wall thinner. But we should not forget about other edges - ones, which will make another wall for us. Undoing now is not an option… We need to move the edges. But if you move only those visible at the Top Ortho view, you will forget about the ones at the bottom and screw the model. And selecting all those edges one-by-one is not an option too…

Selecting many edges manually is a pain...

Moreover, we do not see those edges at the bottom! This is easy to fix, though: see the small button with rectangles near the vertex/edge/face switcher?

'Limit selection to visible' switcher

Click it and you will be able to select bottom edges without the need to rotate the camera. And now we will try the circle-selection tool, which will come to help you when you need to select many elements at a time. Hit the C key and you will see the circle in a workspace. Try dragging it (left-click the mouse and drag) over the edges we need:

Circle selection

Hmmm… It’s way too much… Now, hold the Shift key and drag the circle over the neighbour, redundant ones:

Unselecting elements

Now we can switch back to the Top Ortho View and successfully move our edges:

Making walls thinner

Now that we have our walls precisely set up, we can extrude the last two walls. Select the Normal coordinate system and perform the extrusion along the Z axis:

Extruding last two walls

Now we will scale our model a few times. Staying in the Edit mode, select all the faces with the A key:

Selecting everything

And hit the S key and start entering scale factor number. That’s right, just press, say, 5:

Entering factor while scaling

You can correct what you entered using the Backspace key. You can do the same thing while moving or rotating elements. This is useful when you need to make operation really precise. But you still can use your mouse, of course.

Hint: if you scaled your model outside the Edit mode, you may find your scale, translation or rotation different from identity values (1, 1, 1 for scale or 0, 0, 0 for position/rotation). This may cause different bugs while exporting models. To fix this, you need to select your model in the Object mode, hit the Ctrl+A and select Apply Scale (or whatever you need to fix) from the pop-up menu.

Applying scale

Texturing our model

Now we need to paint our model to have something more beautiful in our application than just pitch black… stuff…

Adding textures to a model in Blender is extremely easy - you just select your model, switch to the Texture tab on the right panel and click New button:

Creating a texture

Then you pass in some params like texture size, the background color and image name - and you are done!

New texture params

But that will only add a blank texture. And then you will need to paint it as you wish. But painting a texture requires your model to have vertices, synchronized with your texture. So each vertex will know where it lays both in 3D space and on the texture image. This assignment process is called Texture unwrapping or UV mapping (because texture coordinates are usually called u and v instead of x and y, since those are already involved to describe vertex’ position). And this process requires one thing from you: you need to specify, where Blender should “cut” your model. This is quite simple task, but this will result on how the texture will look like and how easy it will be to paint.

So, go to the Edit mode and select a few loops of edges:

Selecting seam edges

Selecting seam edges

Now, on the left panel, switch to the Shading/UVs tab and click the Mark Seam button:

Shading/UVs tab

This will mark the selected edges as seams to “cut” your model along. Have no fear, your model will not be actually cut - it will be used for maths only.

Then, on the same panel click the Unwrap button and select the first unwrapping method on the list:

Unwrapping method

Again, no effect you will see now. To see something, switch the window layout at the top menu to UV Editing:

Layout switcher

Layouts available

You will see two windows - on your left there will be UV/image editor and on your right there will be the 3D view. And again, nothing interesting here… But I am not fooling with you - it’s only how Blender works… To see something marvelous, select everything on the 3D view:

UV-Mapped model

You will see some lines on your left. That’s what you have selected, mapped onto image plane. But there is no actual image in the UV/Image editor for now. To add one, just click the New button on the bottom menu of the UV/Image editor or select an existing one:

Selecting background image for UV mapping

This will not change the image itself. The image will be the background for our image editor window, nothing more. To start making miracles, go to the Texture Paint mode in the 3D view:

Texture Paint mode

And your model will change its look…

Pinky!

What is this pink monster?! Well, on the left panel of our 3D View there’s a message, saying the texture slot is missing and proposing to create one… Let’s do this…

Texture slot creation

Now we are able to paint our model! See, how awesome it is: you have a brush tool activated. Brush has three params:

  1. Color - this could be changed with the color circle below
  2. Radius
  3. Pressure, or Alpha

Radius could be changed by pressing the F key and moving mouse cursor:

Brush radius changing

Pressure could be changed by pressing Shift+F and doing the same:

Brush pressure changing

And you can just pain like in… Microsoft Paint!

Just paint!!!

But if you look into the UV/Image editor, you will see… nothing! Again! ‘the hell?!

WTF?!

That is just misunderstanging - you were painting on the other image instead of the selected one:

Choosing image for UV/Image editor

We created a new one, when created a texture slot…

To start drawing in the UV/Image editor instead of 3D View, you just need to switch its mode to Paint at the bottom menu:

Painting in the UV/Image editor

Okay, so far so good. We are able to paint our model. But there’s one interesting thing: if you try to draw a straight line - you may face situation, when line is straight in the image but is curved on the model:

UV mapping mistakes

UV mapping mistakes

But that’s happening not everywhere - only on certain faces/edges:

Mistakes are only on certain faces

Well, that’s because of UV mapping is not precise enough. If you switch to the View mode in the UV/Image editor and to the Edit mode in the 3D View, and select all the model, you will see the points in the image editor, you may drag:

Control points in the image editor

Try selecting them with Right mouse button and moving them with G:

Selecting control points

Moving control points

Yes, now texture looks creepy, but lines are almost straight:

Fixing UV mapping errors manually

Fixing UV mapping errors manually

Exporting our model

When you finish painting your texture, the last thing we need to do is to export our model to the format, understandable by Irrlicht. For good, both Blender and Irrlicht support many different formats:

Blender exporting

Blender’s file dialogs look differently, but have very intuitive interface:

Blender file dialog

If you do not see the needed format in Blender - you just need to turn on a corresponding plugin:

Blender settings menu

Blender settings menu

After exporting our model to, say, 3DS format, take a look at the directory you have exported your model to:

No textures!

Where are the textures? Relax, they are in the UV/Image editor, yet unsaved. You can save the modified image with the Image -> Save menu at the bottom of UV/Image Editor:

Saving image from UV/Image Editor

Now we have everything we need for our Newtonian sample!

Next chapter