EZ3D Designer Quick Start

Introduction

EZ3D uses a three axis coordinate system where all three axes are at right (90 degree) angles to each other. The directions are named X, Y and Z. These are just names. They could’ve been called North, East and Up. A shorthand notation is often used for these three names. For example (x,y,z) = (5,10,15). The term "vector" is the same thing as "(x,y,z)".

It might help to print this file. It is about 6 pages long and is designed to be printed from your web browser.

Beginning

Start EZ3D. You will be presented with a blank drawing with two green lines. The horizontal line represents the X-axis  and the vertical line represents the Y-axis. There is a Z-axis but you can’t see it yet.  It is perpendicular to the screen. For now, imagine the Z-direction as the “depth of the screen”.

Most new users are going to want to take a look at the enclosed data (*.3d) files first. That's fine, but please take a look at the 3-D view (Menu>View>3-D View) for each file. Some of the files won't make much sense if you don't.

Tutorial

If you work through this, you will know about 80 percent of what you need to know.

Insert a solid rectangle (also called a box). Menu > Insert> Solid> Rectangle. Click OK to accept the defaults.  You should see a rectangle. This is the front view of a box. Take a look at the box in 3-D.  Menu> View> 3-D View. You should now see an oblique view of the box.

The Zoom In (+) and Zoom Out (-) buttons are in the ToolBar. Try them.  There is no limit on how many times you can do either of these.

The "Green L" in the ToolBar is for moving the origin. Click on this symbol and then click anywhere in the window. The origin will jump to that position. Suggestion: repeat this several times to get used to it. It is something you will do often. The Zoom in (+) and Zoom out (-)  toolbar buttons will also be used frequently. Insert a second box adjacent to the first. Repeat step 1 but this time change X-origin to 30. The “30” is the width of the first box. Click OK.

 Now move the first box to sit on top of the second box. Select the first box by clicking on any line representing the first box. It should become highlighted. Menu> Edit> Dimensions will bring up an edit box. Change X-origin to 30 (X-origin of second box) and Y-origin to 40 (height of second box). The numbers 30, 40, and 50 are just some numbers I chose that lie somewhere between very very small and very very big.

Insert a vertical cylinder right through the center of the two boxes. Menu> Insert> Solid> Cylinder will bring up the New Cylinder dialog box. First, click OK to take a look at the default cylinder. Select the cylinder by clicking on any line representing the cylinder. Menu> Edit> Dimensions will bring up the Edit Cylinder dialog box. Change the X-origin to 45 (box width + box width/2) and the Z-origin to 25 (box depth/2). Set the cylinder length to to 150 and the diameter to 5. Click OK.

Oops, there's been a mistake. The cylinder is aligned in the X-direction. Click on the cylinder and then Menu> Edit> Dimensions. Change Axis Direction from 1 (X) to 2 (Y).

Put a cone on the top end of the cylinder. Menu> Insert> Solid> Cone. To position the cone, change the X-origin to 45 and the Z-origin to 25. These are the same X,Z values as the cylinder. Change the Y-origin of the cone to 150. This is the top end of the cylinder. Change the cone Base 1 diameter to 250, the length to 30, and the axis direction to 2(Y). Change the number of facets to 64. Click OK. Play with with this number to see what it does. Cone Base 1 is the base that contains the origin. You can see this with Menu> Settings> Show Origins.

Finally, create a new box using "Duplicate" instead of "Insert". Click on the bottom box and then Menu> Edit> Duplicate. Change the Width (x) to 80 and the X-origin to 60. Click OK. Try coloring some of the components with Menu> Edit> Color. Try Menu> Settings> Show 3-D Compass. The three needles are always parallel to the X, Y, and Z axes.

You can print the work at anytime, but I strongly suggest printing via the "Print Preview" option. The drawing may need sizing and positioning before printing. The 3-D Compass does not print very well. You may want to turn it off before printing.

Save the drawing and give it a name. The option Menu> File> Save As will let you give it a name. Optionally, you can also create a folder to put it in.

Selecting a Component

You did this in the tutorial but a little more info might be useful. To select a component, click on (or near) any line representing that component. A miss ditance of about 5 pels is allowed. The component should become highlighted. If a mouse click misses all lines completely, anything selected will be deselected and its color will be restored to the original color.

The highlight color is a sort of gold color. I chose that color to stay off the beaten path so to speak. Objects can be colored by the user. There are 16,777,216 colors and I chose to stay away from the popular red, green, blue, cyan, and magenta etc. as the highlight color. If there is a colored object that you can't distinguish it's color from the selection color, you will just have to remember which is the selected component.

The Zoom Point (Center of Interest)

As the name implies, the zoom point represents a homing point that is set by using the Zoom Point button in the toolbar (magenta cross-hair inside a square). However, it is far more than that, and so much so that I didn't want to use the term "zoom point". Instead, I call it Center of Interest, or simply COI. For one, it is a "3-D point" in the sense that it has x,y, and z coordinates. It also becomes a temporary origin for the entire drawing. Any view angle changes (rotations) turn about the COI. The default value for COI is the origin and shows up as the magenta cross superimposed on the green axis lines. To move the COI to a different position, click the zoom point button and then click anywhere else on the screen.

Alas, there is something missing. A mouse click returns only two bits of information, the (x,y) screen coordinates. This is not enough information to establish the needed third coordinate z. To establish z, simply switch to another view and set the COI point again via the toolbar button.

Please do not dwell on this subject. The "SkyScraper" exercise that follows is a whole lot easier to comprehend.

The Trapezoid

A trapezoid is a 4 sided figure (a quadrilateral) with 1 pair, and only 1 pair, of opposite sides being parallel. This is a pure mathematical definition. It excludes parallelograms and rectangles because these shapes have 2 pair of parallel sides. It also excludes triangles. Relaxing the classic definition a bit allows the inclusion of parallelograms, rectangles, and triangles as being trapezoids. In EZ3D, a solid trapezoid is a trapezoid with thickness. That is, it has two parallel faces.

Start EZ3D and insert a trapezoid with Menu> Insert> Solid> Trapezoid. Click OK to accept the defaults. Insert another trapezoid. "Top Line x-shift" is the displacement of the top line relative to the bottom line. Change this from 5 to -5 and change X-origin to 60. Click OK. Like cylinders and cones, solid trapezoids have a direction. Insert a third trapezoid. Change the X-origin to 120 and and align the base with Y (2). Add a fourth. Change X-origin to 180 and align the base with Z (3). Take a look at the 3-D view.

It should be clear that you can make rectangles and parallelograms by setting the Top Base Line Length equal to the Bottom Base Line Length. You can make triangles by setting either one of the base line lengths to zero. Insert another trapezoid. Change the Top Base Line Len to 0. Place it at X-origin = 0 and Y-origin = 60. Click Ok.

While still on the subject of triangles, You can make right triangles by setting the x-shift to zero or to the value of the bottom base line length. You can make isosceles triangles (triangles with 2 sides of equal length) by setting x-shift to 1/2 the base line length. You can turn triangles upside down by setting the bottom base line length to zero instead of the top base line length. Of course you can also change the direction to align along X, Y, or Z.

The Edit> Rotate Command

You can rotate any 3-D point about any other 3-D point about any 3-D angle in 3-D space. On top of that, the entire drawing can be rotated. That sounds pretty heady, but fortunately, the solution to a problem usually turns out to be a lot simpler. Most problems involve a rotation about a single axis. That is, it behaves like it's hinged. The "10 inch dob" exercise that follows is a good example. The "HalfCube.3d" exercise involves a double (2-axis) rotation.

Examples / Exercises

The SkyScraper

This is an exercise in using the Zoom Point. It should be kind of fun as well. Load "SkyScraper.3d". At the top of the mast is a red light. From the Front View, set the zoom point there and zoom in until you recognize it as a red cylinder. On the top floor is a psychiatrist's office. Zoom out until you get a good view of it. Again, from the Front View, set the zoom point on the center of the office. Now switch to the Side View. Notice the zoom point is not close to the office. If you start zooming in, the office will quickly drift off the screen. This happens because the Z-component of the zoom point has not been set yet. To establish it, set the zoom point again from the Side View. You can optionally do this from the Top View. Once the Z-component is established, you can view the office from any direction at any zoom value. The thing to remember is that the zoom point stays at a fixed position on the screen and the origin moves.

Switch to the 3-D View and start zooming in. You should recognize the patient's couch, the doctor's chair, and his desk. On the desk is a computer. Set the zoom point on the computer screen. (Note: depending on how you got here, you might have to zoom out and refine the zoom point location using different views.) Start zooming in. On the screen is "Hi". Set the zoom point on the dot over the "i". Zoom in. It's another red cylinder. Turn "Hi" upside down. From Menu> Settings> 3-D View Angles, change Rotate about Z to 180 degrees. Start zooming out, way out, until you recognize a blue diamond. It is upside down. Change Rotate about Z back to zero degrees to upright it.

The Dobsonian Telescope

Load "10 inch F6 Dob.3d". This is the same file that I used in making the introduction to EZ3D Designer. This particular lessen is about component rotation. Take a look at the various view directions (Front View, Side View, Top View, and 3-D View). Stop on the Side View. The optical tube assembly (OTA) is set to an elevation angle of 30 degrees. Click on any part of the OTA and then look at Menu> Edit> Rotate. You will see that the rotation angles about (X,Y,Z) are (-30,0,0) and the pivot point is at (0,25,0). The minus sign in the 30 degrees is required because we are rotating about the X-axis which is normal to the screen and pointing inward. This is a consequence of the Right-Hand-Rule. The pivot point (0,25,0) is the center of the elevation axis. You can see that by selecting either of the elevation bearing disks and viewing Menu> Edit> Dimensions. The X-value plays no part when rotating about only the X-axis. It is probably best to set it to zero.

All of the parts making up the OTA are rotated by the same amount about the same pivot point. Try changing the elevation angle of the OTA by clicking on each component one at a time and changing the rotation angle to say (-45,0,0). You will see each component being rotated. Doing this in the 3-D view is interesting. There are 15 components to rotate but this goes fast.

The Half-Cube

"HalfCube.3d" is an examples of a hinge riding on another hinge and is perpendicular to it. It is a silly little problem that can tax you imagination. The object is to fold this pattern into a "half-cube". A half-cube consists of the three faces of a cube that are perpendicular to one another. There are many ways to do this, but in this problem, you are not allowed to use translations. It must be done with rotations only. The size of the cube is 30x30x30.

Here is one solution. It helps to turn on "Show 3-D Compass", "Show Origins", and "3-D View". Rotate the green face about Y by 90 degrees. Edit> Rotate (x,y,z) = (0,90,0) degrees. Pivot point = green origin = (30,0,0). Rotate the red face about both the X and Z axes with Rotate (x,y,z) = (-90,0,90) degrees. The pivot point = red origin = (30,30,0).

Musings

There are times when you can't see the component you want to select. It could be hidden behind another. Try different views to see if that exposes it. Fortunately, this step works most of the time. If it doesn't, try selecting components near it and hiding them with Menu> Edit> Hide. It may have been hidden already, so try Edit> Menu>Unhide All. Drawings typically have components with shared lines. Some or even all of these lines may have covered up the selected object. Again, hiding components usually works. Sometimes you can see it but can't select it because the lines are so numerous and so dense. Selecting a line making up an object allows a small miss-distance which can cause it to select a component other than the intended one. Zoom in on the component and then select it.

When using the Edit> Rotate option, you may choose to use the origin of the component as the point of rotation. If so, you need to make sure the pivot point stays the same as the origin. Picture this sequence: Insert a component and rotate it with the pivot point set equal to the origin. Move the component using Edit> Dimensions. If you do not update the pivot point position, you are going to see some strange and confusing behavior on the location of the component.

If you are using the Center of Interest (COI), zooming way in, and switching view directions, it is easy to get totally lost. This is usually the result of not updating COI using two views. To recover, use Menu> Edit> Reset Zoom Pt., center the origin with the Set Origin toolbar button and then zoom out. This should get you close to where you started.

Future Plans

There are some options in the menu that have not been implemented. For example, in the Insert menu there is a mention of inserting solids, surfaces, lines, and points. Only the solids have been implemented. The others are somewhat muddled in definition. This is a 3-D ONLY drawing program. It is not clear to me as to what, in general, a 3-D surface is. The same is somewhat true of lines. You can restrict lines to be straight lines. Even so, I can only picture using them as phantom lines such as dimension lines, center lines, reference lines, and so on. I cannot think of much to do with a point other than to use two points to make a straight line. I am speaking in the context of EZ3D Designer. It's real purpose is in designing using solids.

I have not gotten around to Cut, Copy, Paste using the clipboard either. There are some issues here. At least I've done Delete and Duplicate within a single document.

Tom Stokes - December, 2008.