Finished project of CeMac

The story behind this model and its purpose goes like this: “Hello Jim, this is your mission if you decide to accept is, build a Ceiling Mounted Automatic Cannon, or better known by its buzz word, CeMac!”

As the smoke from the self-destructing mission briefings DVD burns your nostrils, you quickly sketch out the design on some toilet paper so it you can flush it, or swallow it, in case you get caught with the design.

Figure 1.0.1 Sketch of model to build

Figure 1.0.2 Views Icons and 4 View choice

Figure 1.0.3 Cylinder Primitive options with right clicking

We will be using this method to set the cylinder primitive. Type in 1 for the Latitude text box option. Type in 12 for the Longitude text box option. If there is any number besides 1 in the Top Radius text box option, type in 1. After you have set your options correctly, you will now activate the Cylinder Primitive Icon so you can use it. Move your cursor into the Top viewport and try to left click in the center of the grid. You may be wondering what the red and green bars are for when you create the primitive. If you click somewhere off of this primitive, they will disappear and you may accidentally create another cylinder primitive as you are still in Cylinder Primitive creation mode. Take a look at Figure 1.0.4 to see an illustration of these bars and what they are, and a taper effect it could create if you click and drag the green bar.

Figure 1.0.4 Taper and Scale effects of clicking and dragging bars

Now you need to click on the Object Tool to deactivate the primitive creation tool. If you don’t deactivate it, you will keep creating cylinder primitives! (In case you do not know where this tool is, see Figure 1.0.5).

Figure 1.0.5 Object Tool location

To continue onto make the base of our CeMac, we will be using features of GameSpace to make it a bit easier. You can hide an object from view in what is called the Scene Editor, or sometimes referred to as SE. Click on the Scene Editor Icon as shown in Figure 1.0.6.

Figure 1.0.6 Scene Editor and how to hide an object

If you click on the Visible setting, it will hide the object from view that was highlighted by its selection in the scene. There is one problem though; you could still accidentally select it, even though it is hidden! To avoid this with overlapping objects, its best to use a handy feature of GameSpace, called Layers. Layers can contain objects that you can hide and lock, to keep from selecting and seeing objects that are in a layer. Layers can even have a color so you can see the objects in these layers with a wireframe of this color you haven chosen. You do this by right clicking on a layer icon and use the color wheel to change its color and the wireframe color the objects. Lets create a new layer, and put this cylinder in it now to avoid what we just discussed for the future creation of our model. Click on the Add New Layer Icon as shown in figure 1.0.7.

Figure 1.0.7 Add New Layer Icon and color options

Now we will change the options on the Scene Editor to make it easier to move objects to different layers. It is pretty simple in the Scene Editor to change an objects layer. You click and drag an object to the layer of your choice and drop it on the layers as Figure 1.0.8 shows how to do this.

Figure 1.0.8 Changing objects layer order in the SE

Now you can lock off the layer and hide it as well. The best part of this way of doing things is, that you can hide, and/or keep from selecting multiple objects and have objects that are related to each other into a layer for ease of use. Let your imagination run wild!

Take a look at Figure 1.0.0 for a demonstration of how to Lock, Hide, or Show a layer.

Figure 1.0.9 Changing Layer properties

You will now Lock this new layer by clicking on the Lock icon from the flyout menu if you haven’t already done so.

Note: If you have hidden the object by using the method of right clicking on the object and unchecking Visible, you may get confused when you also have hidden the layer. If you do this and try to make the object visible, it will seem to not work and get you frustrated, as the layer was hidden and will not allow objects in the layer to show until you click the Show Layer in the Layer properties.

Try selecting the cylinder. You will find that its impossible to select this object as it is on a locked layer. For now unlock the layer so we can still work with it.

Before we go on, a word of advice is warranted here; save your work before you do any major changes to your work. I always save in steps, and saving them to a directory by the models name. So for example if I were to make a Boolean operation and the file name was “gat10.scn,” I would do a Save As before attempting it and name it “gat11.scn.”

Figure 1.2.0 Light Icons, placement and settings

We need to do one last thing before we are ready to shape this cylinder primitive. The material of this cylinder may be still to dark to be a cold metal look. You will change the material by clicking on the Material Editor Icon, (ME), then open its properties. You could apply the texture to this cylinder at this point. You can do this by opening the image browser, then dragging and dropping the image into the ME. To apply this new setting or material, you will drag it to the cylinder as shown in Figure 1.2.1.

Figure 1.2.1 Material property settings

Once you have dragged and dropped the new material, you will see the image applied to the shape. It is incorrect, and we will fix it later. For now just turn off the view of the texture by right clicking on the Draw Icons, and clicking on the Toggle Use of Textures in Solid Render Icon in the options, like Figure 1.2.2 shows. This only works for the active viewport, so you will have to do it for each one that you wish not to see a texture on an object.

Figure 1.2.2 Display options property settings

Before we will work on this, move the shape up above the floor of the scene, as we will be working on the bottom of this object. The object must be selected. You may have noticed a blue selector cage around the active the object, and wondered what its use is. You can use this to scale, or rotate the object, as you desire. I will not go into detail of its use, but you can read more on it in Chapter 1 Introductory Tutorials under the subheading “1.2 The Selector Cage,” page 3. Simply click and drag the object up.

We will be exploring the use of the Sweep tool, or in some modeling applications known as extruding. This is a powerful tool, as it can add sections to your model, so you can shape more complex models. Model makers often use this type of tool.

The icon to access this tool is currently grayed out because you are not in an object’s editing mode. To do this, first select the object that wish to edit, and then right click on it. You are now in the Context Editor mode and should see a wireframe and a see through look to the object now. There will also be a new set of Icons to use for editing the features of any object. These include Face, Edge, and Vertex modes of editing an object. There are 4 ways to select a portion of the object: Freehand, Lasso, Rectangle, (window selecting), and Named Selection. If you do not select any, you will be in a Context Edit mode, which is very handy as you can move your cursor over any of the above mentioned portions of what makes up a object.

The next step will allow you to see all available icons for your use, instead of having to click and hold and then navigate up, or down the icons flyouts. On the edge of any toolbar, you should see a dotted looking vertical bar. Click only once on this. (If you do it twice, it may collapse the entire bar as one dot, which is hard to find sometime. You would need to click on this dot to bring the toolbar back to show its icons if this happens to you). Now you can select the faces of the object without fear of selecting anything on the bottom or sides that do not face your cameras view of the viewport. Click on the top of the cylinder to select the polygon at the top of the cylinder. In the context editor, you will see the Sweep tool. Click on it now, as it has a default sweep setting. (You can right click on it to type in values if you wish). See figure 1.3.0 to see how to do this.

Figure 1.3.0 Entering Context Editing mode

We now have to control the sweep, or extruded face we have selected. Use the Selection cage to move it upwards, until it is pretty close to the original. Click the Sweep Tool once again. Now you’re going to use the Selection cage to scale this inwardly, and then move it up to be level with the last sweep to make the start of an indentation for our motion detection area of our CeMac. Figure 1.3.1 shows the details of these sweeps, moves, and scales using the Selection Cage.

Figure 1.3.1 Using the Sweep Tool and Selection cage to shape object

Before we continue, pull up a chair and get a cup of coffee as I am going to give you some pointers on Low Polygon Modeling, or as some call it by the buzzword LPM. When you are working with a game engine, you need to be concerned on how many triangles are in a model. (Triangles are sometimes considered as polygons in modeling but polygons can have more than 3 sides or edges to them, so be careful when your doing a polygon count. Your export of your model will probably use a triangulate on the polygons that may contain more than two triangles. Quads as they are known in the modeling community consist of two triangles to from a rectangle shape. GameSpace uses a technique while modeling to use more than one triangle to make complex shapes easier to work with). The game engine has to keep track of all of the polygons in use, no matter if they are displayed or not. It uses a routine to do what is called backface removal before trying to draw these polygons on your screen. This can take up a lot of unnecessary CPU time, so you should rid the model of polygons that will never be seen ingame.

Done with the lecture now, so while you still have that top polygon selected, switch to the Delete face, then click in the top viewport on the selected face you have been working with up to this point. (See Figure 1.3.2). A player will never see the top portion, as this is a Ceiling Mounted automatic cannon! Click on the object tool to deselect to get out of Context Editing mode.

Figure 1.3.2 Face Delete Tool usage

If the base portion of the CeMac is not still selected and you don’t see the selector cage around it, click once on the base. If the X and Z Navigation Toggles are not turned off, turn them off now, as we want to move only in the Y direction. Click and drag away from the selector cage to move the base up off the floor of the scene. You can refer to Figure 1.4.0 to see approximately how high, but first we will create a cube to use for our Boolean operation.

Switch to a screen mode by clicking on the Display Options Icon and then move your cursor up to the Draw objects as transparent outline icon. (Refer to Figure 1.2.2 for a refresher on this).

Create a cube that is only 1 x 1 segment. Refer back to how to set up a primitive at the beginning of this article if you need to see how this is done. (See Figure 1.0.3 for a refresher). Click on the Object Tool to deactivate the Magic Ring mode of the primitive. If you accidentally deselect the object, (you do not see the Selector Cage), click on the cube once to activate the objects Selector Cage. We are going to squash this cube by its X, and expand it by its Y axis. Move your mouse cursor to the front view and close to one of top left edges of the cube until you see it change to a cursor with an up and right arrow. (You may see the cursor change into other shapes, but move it until you see it take on the aforementioned shape). You should now be ready to squash it on its X axis. Move this edge until it approximately what it appears in Figure 1.4.0. Now do the same for the top edge, and expand it until you have it just a wee bit into the base that you created earlier. Move your cursor over, but don’t click the cube you created, and press Ctrl c to make a copy of this cube. We want to be able to scale this copy by keeping it centered to the first copy to for accuracy. Now you will need to set up this cube to use as a subtraction for the Boolean operation. Scale it on its X axis, then scale on its Z axis as well to make it larger in depth. Move it down by its Y axis as shown in Figure 1.4.0. You are now ready to perform the Boolean Subtraction.

Figure 1.4.0 Copy, Scale, and Boolean subtraction

I hope you’re ready for the magic of Boolean operations! 1^st click on the object you wish to keep. Next navigate to the Boolean Subtract tool. Finally, click on the object you wish to use as a subtraction from the first item. You can follow these steps as in the illustration of Figure 1.4.0.

Are you ready for a tool that is not found in other modeling utilities that is very useful? I was pretty excited about it when I found it. It’s called the Polygon Copy tool in the Context Editor. Another useful tool is the Polygon Draw, but I will leave you to look up how to use this in another tutorial or the manual that comes with GameSpace. We will only use the Polygon Copy tool.

Figure 1.5.0 Polygon Copy Tool usage

You may need to scale this polygon up in size, so click on the Point Scale Tool to do this and click and drag with both mouse buttons. If you need to move this polygon to look more centered, click on the Point Move tool and move it around until it looks best. Refer to Figure 1.5.1 for what these tools look like in the Context Editor.

Figure 1.5.1 Point Scale, and Move Tool Icons

Usage of the Sweep Tool is the next order of business. Click on the Sweep Tool to sweep this polygon outward and move it to look like a pivot point for the AC.

Now you will need to do this to the other side of the bracket for the CeMac. Just follow the same steps, but when you are ready to scale and move the polygon, try to line it up with the opposite sides, while you’re in Draw objects as transparent outline icon. If you forget how to do this, refer to Figure 1.2.2 and the text above it as a refresher on this. After your second sweep operation, you should have what Figure 1.5.2 shows.

Figure 1.4.4 Finished bracket

The next step will be to create the AC component of the CeMac. We will be using the Point Edit: Vertices Tool in the context editor to achieve the look of this for low polygon use.

Sooner or later, it will come to editing at the vertex level, the smallest component of 3D modeling. And in this section we need to create a cylinder primitive and scale some its vertices down in size to create the illusion of a 6-barrel automatic cannon. But first our bracket looks a bit to large so let’s review our Point Edit: Scale option of the context editor. If you’re still not in the Context Editor mode, right click on the bracket. Click on the Point Edit: Faces Icon and the Select using rectangle Icon. Make sure the Backside option is checked in the selection options. (Right click on the Select using rectangle Icon if you have forgotten how to access this feature). Drag a window around all of the faces to select all. Click on the Point Edit: Scale Icon. Make sure all the Navigation Toggles is turned on. (As a reminder refer to Figure 1.4.1 to see where these are located). Now click and drag down and to the left to scale it down. Click on the Point Edit: Move Icon, and lock off the X and Z Navigation Toggles. Move the bracket back up into the base of the CeMac. Now create a Cylinder Primitive that is 1 Latitude, 12 Longitude, and 1 Radius segments in proportion. Use the primitives Magic Ring to scale this down to fit inside of the bracket. You will need to rotate this, and we will be using the object info dialog to do this. Right click on the Object Tool to bring up this dialog and type 90 in the X Rotation axis. Take a look at Figure 1.5.0 to see how close you come to what the image depicts.

Figure 1.5.0 Using object info for rotation

You could also use the object info dialog to move, and to size the object. You can even use math operators on the Size, Rotation and Location axis, e.g. if you type /2 in any of the Size axis, you would scale the object on that axis down to half its size. You could also use the Selector Cage to rotate the object, and combine the Grid snap feature to help to make it snap in a orthogonal way.

Enter the Context Editing mode by right clicking on the cylinder primitive. Select the front face. Click on the Sweep tool. Use the selection cage to move this sweep outward ly to look like Figure 1.5.1.You should try to make the whole of bracket and AC center to the base. Click on the Object tool to deactivate the context editor, and hold down the Ctrl key and click on the bracket and move the bracket and the AC on the X axis to center it. See Figure 1.5.1 to follow these steps outlined in this paragraph.

Figure 1.5.1 Sweeping and centering the AC

To use the Separation tool, you will need to select only the cylinder or the AC part of the gun. Click on the object tool until nothing is selected. Then click on the AC cylinder, and right click on it to enter Context Editing mode. Click on the Point Edit: Face Icon and the Select using rectangle Icon. Select on the part that you made with the Sweep tool previously. Click on the Separate selected part of object Icon. You will see a piece of it separate and close both portions with a face of its own. Take a look at Figure 1.5.2 to see how this was done.

Figure 1.5.2 Separating a portion of the AC

We will be scaling this down, but only on two axes. Turn off the Z axis in the Navigation Toggles, (located at the bottom right). Move to the front viewport and click and drag with both the right and left mouse buttons. Scale it down as shown in Figure 1.5.3

Figure 1.5.3 Scaled down part of AC

The separated cylinder needs to have twice the amount of edges that it presently has. We will use the Quad Divide Tool to do this. Click on this tool now. Right click on it to enter the context editor. We have what we want, but we need to get rid of the extra stack that it created in the middle of the cylinder. This is pretty easy if you use the tool that you are already familiar with, the Separate Tool. Click on the Point Edit: Face Icon and the Select using rectangle Icon. Do a window select on the back portion of the cylinder to select all the faces. Click on the Separate selected part of object Icon. The editor will deactivate as before and have the separated portion selected. Delete this by pressing the delete key on your keyboard. Click on the remaining portion of the cylinder and right click on it to enter the context editor once again. Take a look at Figure 1.5.4 to bring you up to speed on what we have done so far.

Figure 1.5.4 Quad Divide and Vertices select and move

Select the faces in the front. To make sure you only get the front faces, open the Selection properties by right clicking on a Select using icon in the Context Editor, and uncheck Backside. A good tip here would be to use the Grid Snap mode. Click on the Grid Toggle Icon to turn this feature on. This will allow you to be more precise in your creation. Click the Sweep tool. Move these new faces all the way back to align them with the faces your sweep started from, meaning flatten them on the Z axis plane. Also scale them down in size by using the Selector Cage, (see Figure 1.6.0).

Figure 1.6.0 Selecting, sweeping and scaling faces

On to editing in Point Edit: Vertices mode. I know you have been waiting a long time for this! To make the shape of the Auto Cannon gun look like it should, you will need to select only a few of the vertices from the front and back. Click on the Point Edit: Vertices and the Select using rectangle Icon. Do a window select on vertices as illustrated in Figure 1.6.1 and snap and weld the vertices together. Use the Weld Vertices Icon to snap and weld them together.

Figure 1.6.1 Corrected vertices to form a hex shape

Repeat these steps to go around full circle, welding 3 vertices in the same manner until you have what Figure 1.6.2 shows. You will have to adjust these vertices by moving them around to make the Hexagon shape. Hint: use the scale on some of them with either the X, or Y turned off to flatten vertices in a direction. Also turn of X or Y axis to move them.

Figure 1.6.2 Corrected vertices to form a hex shape

Before you start this next step, I will give you a hint to increase your speed in making models in GameSpace: use the space bar to deactivate the Context Editor after you do a sweep and scale then to right click to enter the Context Editor once again. This is because it seems to want to use the settings of your manipulations and can cause needless tweaking after you do a second sweep. This will not always have to be done, but in the creation of metal looking parts, this is the best method I have found to work. To create a bolt and rotational axis for the AC part of the CeMac, you will sweep this face out, and move it into position so that it will just protrude just a bit away from the gun barrels. Use the familiar Selector Cage to help to do this. Sweep it again, move it back to meet where you swept it from, and scale down. Sweep once more. Look at Figure 1.6.3 to see the final look of how I accomplish this.

Figure 1.6.3 AC details

Time to turn the Backside option on again for this next step. Select the vertices as shown in Figure 1.6.4 and scale them down to form a sort of flower shape.

Figure 1.6.4 Forming the barrels for the CeMac

It’s starting to look a lot like what we envisioned now! One last thing we should do before starting another section is to apply a more of a flat shaded look to the cannon. Click on the Material editor as Figure 1.2.1 illustrated. There are two Icons near the lower right of the Material Editor that has to do with how the materials shading will be applied. We are looking for the Faceted setting in the 2^nd from the bottom icon, and the Sphere on the bottom right icon. Drag the color slider to a gray value of about 148 on all the rgb colors. Drag this new material to the AC. Figure 1.6.5 shows the desired results.

Figure 1.6.5 Material change to Faceted on AC

Figure 1.7.0 Gearbox add to bracket

Create another cube and scale it down in size to make a small block to be used as a pivot bar. Enter Context editing mode and select the top vertices and move them up to meet the inside of the gearbox just created. Apply a white flat shaded material for this bar. You will need to move and rotate this bar to make it fit the gearbox, but you have all the necessary information now to do this on your own.

We need to create an axial device for an arm to swivel on. Create a cylinder with the number 8 in the Longitude setting for the cylinders property options. Create this cylinder and resize rotate it to fit the end of the pivot bar, and then apply a black material with a smooth shading as shown in Figure 1.7.1

Figure 1.7.1 Pivot bar and axial device for the parabolic antenna

You can copy the pivot bar to make the extension bar that will connect the parabolic mirror to the axial device. Rotate this bar to a right angle to the pivot bar, and move the vertices in the context editor as before to shape this bar so the back edge will set inside of the axial device as the pivot bar does now. Before moving on to the creation of the parabolic antenna, lets take a close look at what it should look like in Figure 1.7.2.

Figure 1.7.2 Parabolic antenna close up

You may notice that it has a somewhat bow tie look to it. The original shape started out life as a Cylinder Primitive. Using the Selection cage helped to create this shape.

Start off with a Cylinder Primitive set to 1 Latitude, 1 Top Radius, and 8 Longitude segments. Use the Magic Ring to scale it down to size. Click on the Object Tool to get out the Magic Ring mode. Right click on this to enter the Context Editor. Click on the top face and click on the Sweep Tool. Move your cursor as shown in Figure 1.7.3, and scale inwardly.

Figure 1.7.3 Sweeping and scaling added section

Now use the selection cage to move this slightly inward by grabbing the middle portion of the selection cage. Press the Space bar to exit the Context Editor, and then right click to enter it again, as this will eliminate erroneous sweeping in the next step. Sweep this section again. Scale it inwardly to give it a taper look. Sweep again and scale outwardly to form a diamond shape. Finally, use the Tip Tool to create a point and then move it down in the front viewport as shown in Figure 1.7.4

Figure 1.7.4 More Sweeps and a Tip operation

Now you will select the side faces and sweep them. Use the selection cage scale feature to make it larger as shown in Figure 1.7.5.

Figure 1.7.5 Sweep and scale of the outer faces

I should pause here to refresh you on how to hide objects to make it easier to work on parts of the model. Create a new layer. Select the start of the parabolic antenna shape you have made. Open up the Scene Editor. Drag this bowl shape to the newly created layer. Hide the base layer. Now all the other parts shouldn’t distract you! I also recommend that you either create a layer for the lights or have all the parts in another layer besides the base layer. This is because if you hide the layer containing the lights, all the model parts will go dark! Refer to Figure 1.0.7 and Figure 1.0.8 for a reminder on how to do this.

You will shape this figure by scaling the ends down a bit. If you remember to exit and enter the Context Editor by pressing the Spacebar, and the right clicking, you can again save yourself some unneeded editing. Hint: you may have to use the Context Editors Scale and Move features if things seem to not work as planned. Use this in combination with the Navigation Toggles to help.

Pull the edges up to start to form the parabolic look to the Antenna. Sweep the edges again. Again scale and move the edges. For the final look snap and weld the vertices as shown in Figure 1.7.6

Figure 1.7.6 Start of the parabolic shape

Sweep once more and move this section up and scale it a bit. Take a look at Figure 1.7.7 to see what it should look like at this point.

Figure 1.7.7 Further shaping

Now snap and weld the ends as Figure 1.7.8 illustrates showing one end and others ready to be welded.

Figure 1.7.8 Welding of edges

Finally, weld the tips together. Exit the Context Editor, and use the Selector Cage to scale this to fit the look of your other pieces. Add one small cylinder so it will look like the bracket you made will be using it to rotate with. (I added a black smooth shaded material to it, to make it stand out more). You should have it looking similar to Figure 1.7.9

Figure 1.7.9 Look at finished CeMac

That’s it! Your finished with the creation of the parabolic antenna for your CeMac! It should look similar to the Figure 1.7.2 that we looked at before we started working on it. Are you ready to animate it? I hope so as this is what the next section will cover.

First, if you haven’t already done so, create a new layer to put the parts of the antenna into a separate layer on its own. This would not include the bracket, or the gearbox. Put only the parabolic antenna, the pivot, axial device and extension bar that will connect the parabolic mirror to the axial device,

Hide all layers except for the one that contains the above items, so they will not accidentally attach to the joints that we are about to create. At this point, I have to give you a gentle reminder. You should save your work and make a backup of it just in case you make a mess of something!

To get this to rotate, first select the axial device. Find the Add shaft joint (1D rotation 1D translation) icon and click on it. You should see the glue cursor appear. Click on the pivot bar. You now should see a joint appear. Congratulations! You now have a joint you can use to swivel your parabolic antenna on. You could test your work so far by clicking and dragging on the Rotation Control that appeared when you created this joint. Take a look at Figure 1.8.0 to see what we should have by now. Again I have to say, save your work before experimenting!

Figure 1.8.0 Creation of joint and Rotation Control

The final thing we will do with this is to glue the other pieces to this joint, so they will rotate with the pivot bar and the axial device. Find the Glue Child Icon. When you click on this, you will see the same icon as before. Take a look at Figure 1.8.1 to see what this icon looks like.

Figure 1.8.1 Glue Child Icon

Now to set the animation. Open the Scene Editor and click on the icon and find the Clip View mode icon. Click on the Auto Record button. Type in 15 in the Keyframe text box. Use the Rotation Control to rotate it the antenna at a 45 degree angle. Type in 30 in the Keyframe text box, and then rotate the antenna another 45 degrees. Type in 45 in the Keyframe text box, and rotate it still another 45 degrees. For the last Keyframe, type in 60 and rotate another 45 degrees. Now try your animation by clicking on the VCR like play button. Woah! You have an animation! Congratulations! Take a look at Figure 1.8.2 for details on the Scene Editor and locations of where these features are.

Figure 1.8.2 Animation using the Scene Editor features

Unhide all your parts and run that animation one more time to see the full thing in action.

One last thing if your going to have a loop of this, you need to move the Timelines Ending Time control back one frame, so if your going to loop this animation, it wont cause a pause that appears as a jerk in the animation. (See the manual Chapter 19 under the subheading The Track Plane for reference on how to use the animation part of the Scene Editor).

Select the base of the Cemac that we already have textured. Right click on it. Select the tapered portion that we first started out with. Click on the UV Mapping Editor Icon. You will now see the portion on a flat plane ready for you to resize and move to a place on your texture that you have created. The UVE is much like the modeling feature we have used so far, with Scale, Rotate, and Move feature and the same selection features as we are already used to. I have just got you started so get to it! You should have it looking like I did. When you have finished with the base, unwrap the AC portion. Take a look at Figure 1.9.0 to see the UVE in action, and the finished product in Figure 1.91!

Figure 1.9.0 Using the UVE by scaling and moving selected piece

Finished product of CeMac