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3DEDIT BETA-VERSION 0.8 IF YOU HAVE ANY QUESTIONS,SUGGESTIONS,CRITISM OR SOMETHING ELSE YOU MIGHT WANT TO SAY ABOUT 3DEDIT, YOU MAY REACH US AT INTERNET: ERIK-TAM@SATURN.DSV.SU.SE MAIL: HUMAN SOFTWARE BRÖTV.42 161 39 BROMMA SWEDEN PLEASE LET US NOW YOUR OPINION. A REAL MANUAL WILL BE RELEASED WITH THE NON-BETA VERSION. THIS DOCUMENT IS REWRITTEN AND ENLARGED ALL OF THE TIME CONTACT US FOR THE LATEST VERSION. -1- CONTENTS 1.BEFORE YOU START. . . . . . . . 3 A. What do I need?. . . . . . . . 3 B. What is 3dedit?. . . . . . . . 3 2.3D-GRAPHICS A SHORT INTRODUCTION . . 3 A.What is an object made of . . . . 3 B.Points . . . . . . . . 3 C.Polygons . . . . . . . . 3 D.Hidden faces . . . . . . . 4 E.Depth Sortint . . . . . . . 4 F.What do I read to learn more? . . . 4 3.VIEWING THE BOAT A SMALL INTRODUCTION . 5 A.Starting 3dedit and loading the boat . 5 B.The screen . . . . . . . 5 B.The buttons . . . . . . . 5 C.Moving the boat . . . . . . 5 D.Rotating the boat . . . . . . 6 E.Leaving 3DEDIT . . . . . . 6 3.CREATING A BOX-A QUICK START . . . 6 A.Starting 3dedit . . . . . . 6 B.Show points . . . . . . . 6 C.The first point . . . . . . 6 D.Moving the point . . . . . . 7 E.Creating a new point . . . . . 7 F.To change an AS to another point . . 7 G.To create a polygon . . . . . 7 h.Changing the view . . . . . . 8 i.The backside of the box . . . . 8 j.Creating the rest of the cube . . . 9 5.CREATING AN OBJECT . . . . . 9 A.Creating points . . . . . . 9 B.Moving points . . . . . . . 9 C.Selecting points . . . . . . 9 D.Destroying points . . . . . . 9 E.Viewing all points . . . . . 10 F.Creating a polygon . . . . . 10 G.Selecting a color . . . . . . 10 H.Selecting a shape . . . . . . 10 I.No backface - Clockwise order . . . 11 J.Back-face polygons . . . . . 11 K.Destroying a polygon . . . . . 11 4.THE PANEL AND THE BUTTONS . . . . 7 6.LEGAL STUFF . . . . . . . -2- -BEFORE YOU START- WHAT DO I NEED? You need an 100% IBM-compatiable PC with a 286 processor or higher with VGA-card and a mouse. Note that the VGA-card must be truly register compatible with the orginal VGA-card from IBM. WHAT IS 3DEDIT? 3dedit is an application designed to make 3ddesign easy and smooth. 3dedit uses polygon-based graphics, which means that each object is made of colorfilled polygons. You've probably seen it in flight simulators etc. 3dedit is a part of the polyworld package, which is a C-library together with tools, made to make true 3d-graphics available to the C-programmer. A Turbo Pascal version may appear later. 3dedit creates and saves objects in a format that G3DLIB can use. Create your own F15, Driving game etc. 3D-GRAPHICS A SHORT INTRODUCTION If you have some knowledge about 3d-graphics, you might skip this part. 3D graphics is in short, to manipulate a model of a 3dimensional object, or group of objects, and view it on a 2dimensional screen. At least, thats whats we are concerned with. In this context we will call an model of an 3d-object just 'OBJECT'. WHAT IS AN OBJECT MADE OF An object in 3dedit is defined by points and polygons. Each polygon is defined by a number of points in the object. This is easier than it sounds, you just have to look at a regular flight simulator to know what I mean. For an example, a box is defined by its eigth corners(the points) and its six sides(the polygons). POINTS A point is located in the 3dspace by its coordinates along the three axis, X-Y-Z. The Z-axis is the axis thats goes 'into' the screen. In 3dedit, you never have to be concerd with the actual coordinates of a point. POLYGONS The polygons are defined by points. In 3dedit you use 2 types of polyons, triangles and quadron(with 4 corners). A -3- face of an object can be made up of many polygons. HIDDEN FACES When you view an 3demonsional object, all faces are never seen at the same time. If you take an box, you can at most see three faces of it at one time. This is quite important in 3d-graphics, because the computer has to know when to show a face or not. 3dedit uses a techinque called backface culling to evaluate which polygons to show and which to hide. To let 3dedit know this, certain steps must be taken when you create an polygon. DEPTH SORTING Since the polygons in an object often overlap each other when the object is displayed, the polygons have to be sorted in order according to the distance from the viewer, before they are drawn. After that, they are drawn in reverse order, beginning with the ones that's most far from the viewer. This is called the painters algoritm. The trouble is that you must choose a point to use as the basis of the sorting. In 3d3dit you have 3 different sort-modes that you have to decide which to use for each polygon. This may sound a bit complicated but trying the different modes should make you get it. WHERE DO I LEARN MORE ? The above introduction certainly didn't make you understand 3d-graphics. But hopefully, it'll make it easier to use 3dedit. If you want to learn more about 3d-graphics there are serveral sources. You can try: Michael Abrash articles in Doctor Dobbs Journal 91-93 Computer Graphics by Hearn&Baker -4- -VIEWING THE BOAT A VERY SMALL INTRODUTION- To get you going, lets start with just loading and viewing an object. The object is named boat.3d and a file with that name should be included in the same directory as 3dedit. To start 3dedit, and load the boat.3d file, type 3d boat.3d. The sceen should go black for some seconds and then you should be able to see the boat at the middle at the screen. The boat is viewed from what the program thinks is the front side. Actually it is the right side of the boat, but the boat was designed from the right side. THE SCREEN The screen is divided in two parts. At the top, it is black, and it's here were you can see the object that you are currently working on. This part of the screen is called the 'VIEW-SPACE'. Below it you can se what we have choosen to call the 'PANEL'. THE BUTTONS As you can see this is covered with buttons. You press a button by moving the mouse-cursor to it and pressing the mousebutton. Most buttons are only activated by pressing the left mouse-button, but some also use the right mouse-button. On thoose buttons, different actions are made by the different mouse-buttons. For an example, the move-buttons uses both mouse-buttons. If you press the x-move-button with the left mouse-button, the object are moved at the right, viewed from the front, and if you press the right one, the object are moved to the left. MOVING THE BOAT Now, lets move the boat on the screen. First of all you have to make sure that the move-object-mode is enabled. This is controlled by a button at the left of the panel, right from the Z-buttons. When you start, this button should be marked with an wire-frame box. This indicates that the move-object-mode is enabled. Try clicking on the button. Now the move-object-mode is disabled and the button should just be marked with a dot. Now click on the button again. The move-object-mode is enabled and the object is ready to be moved. Now you should use the move-buttons to move the object. Thoose are located to the left of the panel, with X,Y or Z below it. By using the button over the X, the object is moved along the X-axis, using the button over the Y, the object is moved along the Y-axis etc. Now, click on the move-button X with the left mouse-button. The boat moves to the right. Use the right and it moves to the left. Use the move-button Z, and it moves away from you. Play around with it for a while. -5- ROTATING THE BOAT Now it is time to rotate the object. Under the move-buttons, you find the rotate-buttons. With these you rotate your object. Try pressing the rotate-button Y and see that boat rotate around the Y-axis. Try the other keys. LEAVING THE BOAT When you are ready to leave 3DEDIT, you just press ESC. The screen should fade to black and yous should be back at the DOS-prompt or whereever you started 3dedit from. -CREATING A BOX-A QUICK START- To get you going, we begin with a step-by-step lesson in the fine art of creating a simple box and to manipulate it on the screen. If you follow this simple quide, you should have learned the basic functions of 3dedit at the time the box is ready. LETS START IT You start 3dedit byt typing '3d box.3d'. Box.3d is the name that we give the file where the object will be saved when we are ready. When the program starts, you will that the upper half of the screen is black and the part below is filled with buttons and stuff. The upper part is where the actual object will be seen, that part we call the 3d-space. The part of the screen that is grey, with buttons, etc, we call the panel. Now if you move your mouse, you will se that the cursor changes when passes over the different parts. SHOW POINTS Click on the Showpoints button. Thats is the third from the left above the CREATE-button. The point in the button should now have changed color from red to green. This buttons turns off/on the showpoints mode. When enabled, all points in the object are shown, blinking white. This slows things down a bit but make the editing of the object easier. THE FIRST POINT At the middle of the 3dspace you can see some dots blinking. Or actually, it is numbers but at the moment they are -6- written over each other. This brings us to the active spots. Active spots(AS) are four different points that you use to manipulate the points in your object. At the panel you can see the numbers 1-4 with a red lamp under each number. When a lamp is green thats measn that the corresponding AS is activated. That means that it is affected by the move buttons and the create button. More of that later. MOVING THE POINT Now click undet '1' at the panel to activate AS 1. The lamp should turn green. AS 1 is now activated. Now click with the left mouse button on the 'move-along-x' button. This is located at the left side on the panel, and is marked with < X >. The point on the 3dspace should move left. Pressing the right mouse button will move the point to the right. Move the point about two inches to the left. Now push the 'move-along-y'button which is right of the 'move-x'-button. Move the point up about two inches. CREATING A NEW POINT Now click on the 'CREATE'-button. Move the new point down about four inches. Note that it is only AS 1 that goes down, the rest of the AS stays with the old point. Now activate AS 4. Press Create and press the x-move-button with the left button. Note that you now have created to new points, one for every activated AS. Move the new points, marked by 1 and 4 to the left until they make the corners of an rectangle together with the old buttons. TO CHANGE AN AS TO ANOTHER POINT Now, we have four points in 3dspace. But only 3 of them are marked by an AS. To move AS 3 to the empty point, the one that is just a blinking pixel, activate AS 3. Then click near the non-marked point at the 3dspace. Now AS 3 should have moved to that point and the numbers 1-4 should be forming a rectangle in clockwise order. TO CREATE A POLYGON Now that we have four points, we could create a rectangle. To do this, you must first change the create-mode. To do this you click with the left mousebutton on icon most to the left above the create-button. This should now change from a point to a triangle. Click on it again and it changes to a rectangle. Now you must choose which color the rectangle should have. Between the panel and the 3dspace you can se a line of different colors. Click at one of the colors and you have now choosen that color to work with. As you -7- probably see, only a part of all the colors available are shown on the screen. To see more colors, you click at one of the arrows at the leftside or the right side of the screen. When you have choosen the color you want to work with, you can now click on the create button. The rectangle should now be visible in all its glory. CHANGING THE VIEW At the right of the panel you can see the seven view-buttons. They're named as X-Y 1, X-Y 1, Y-Z 1 osv. With theese buttons you change the way you look at your object. With X-Y 1 you watch you object from the front, with X-Y 2 you watch it from the back, Y-Z 1 from the above etc. At the bottom you find the free button. With this button you change to free-view, which means that the object can be rotated to any choosen view. The other views are not affected by rotation. You should avoid to rotate the object in thoose views, as it can lead to some problems. Now, change the view to Y-Z 1. You are now viewing the object from the above. Note that you cant see you polygon. Try to view it from the backside. As you are watching the backside of the polygon, the polygon shouldnt be visible. View from the above again. Now make sure that all the AS are activated(that all lamps under the numbers 1-4 are green). Press the move-z-button with the left button. Your four points are moving slowly down the screen. In 'reality' they are not moving down, but along the x-axis, but due to the view, it seems as they are moving down. THE BACKSIDE OF THE BOX Change the create-mode to point, by pressing the icon above the'CREATE'-button, until it changes to a point Now, click on the create button. Four new points are created but you cant see them yet, as they are located at the old points. Now press the move-z button using your left mouse button. As you can see theyre now wandering up at the screen. When you think that you have made a box, click on the X-Y 2 button to view the object from the backside.Now you should be able to create to create a new rectangle, with the four new points. Well, you can, but you wont be able to see it. Why is that? Because the four points need to be in clockwise-order to the viewer, to let 3dedit now that this is the front-side of the polygon. This is a problem. How do you change the order of the points? Well, this is maybe 3dedits biggest problem, which will be solved in the first real-version of this software. But for now, you'll have to change the order of the buttons yourself. How do you do this? Just Follow these simple steps. 1. Change the view to (X-Z 1). CLick oon the number 1 on the 3dspace. The number 1 should now not be blinking. Click on the nearest-point-donmost to the left. The 1 should now have change to that point. -8- 2. Click on the number 3. Now '3' should have stoped blinking and '1' has started blinking as the other numbers. Click at the point where '1' was before and now '3' would have moved over to that point. 3. Click at '1', either on the 3dspace or on the panel. Now click on the point where '3' used to be before. Now the numbers 1 and 3 should have changed place and therefore the order should have turned to clockwise. Change the view to X-Y 2. Now you can click on the CREATE-button, after you have choosen which color that you would want the backside of the box to have. Change the view to free. Rotate the object using the 'rotate-y' button, which is under the move-y-button. Yes thats nearly a cube. CREATING THE REST OF THE CUBE Now that every point that you need for your cube exist, you just have to change the views and create the requiered rectangles, after you have set up the Active Spots to the right points and made sure that they are in clockwise order from the side that should be visible. We know that this isn't very easy to understand from a text. But don't be afraid to experiment, even though we recommend you to follow the steps for creating a box, before you start with your own shapes. If you place a polygon for mistake, you can destroy it with the 'DESTROY'-button. But make sure that the AS really are located at the points that make up the polygon. If you try to destroy a polygon that doesn't exist, the program will crash. -CREATING AN OBJECT- CREATING POINTS Every object must begin its life as points. Before you can create any polygons, you must at least have 3 points. Points are created when you press the CREATE-button and the create-mode is set to points. When create-mode is set to points, the CHANGE-CREATE-MODE button should be marked with a point, not a rectangle or a triangle. Press the CREATE button. Now, a point will be created for each active AS. Example: if you want to create two points, you could make sure that AS 1&4 are activated, that the create-mode is set to points, and then press the CREATE button. Two new points are now created. MOVING POINTS To move points, you have to make sure that the move-object mode is disabled. This is controlled by the button right to the move/rotate buttons Z. When you are able to move points, the button is marked with a dot. It is only the points that are corresponding to active AS that are affected by movement. ECAMPLE: Now, if you want to move the first point you created in the example above, you should make sure that only AS 1 is activated. Move AS 1 to the correct place, and -9- check this from the different views. Then deactivate AS1 and activate AS 4. Move that point to the correct place. SELECTING POINTS If you want to operate on a point that is connected to an active AS, you must connect it with one. To do this you first click on the AS that you want to use. You can either click on the panel or on the view-space. You do this not to activate it/deactivate it, just to let 3dedit now which AS you want to use. Note that on the view-space, the AS you have choosen should not be blinking, but be steady. Now click near the point(on view-space) that you want the AS connected with and the AS should now have moved to that point. This may sound strange but if you only could see it in action, you'd realise how very simple this is. You can also use the + and - keys, but this feature is not very save and not very stable. If you have any suggestions on how we may find an easier way to connect AS with points, please let us now. DESTROYING POINTS At this moment, every point you create is here to stay. In the shareware-version, this feature will exist. VIEWING ALL POINTS By pressing the SEE-POINTS button, you can choose between seeing all the points that the object is made of and not to. When working with the object, seeing the points will make your work somewhat easier. However, this may slow the program down a bit. CREATING A POLYGON. When you are going to create a polygon, you must first have at least 3 points on the screen. The polygon will be created with its corners at the points that are connected with the AS (1-4 for a rectangle and 1-3 for a triangle). SELECTING A COLOR At the top of the panel you can se the colors you can choose from. To choose a color, just click on that color. Since all colors can't be viewed at the screen at the same time, you sometimes have to click on the arrows to the left or the right from the colors. This moves you through the existing palette. SELECTING A SHAPE Currently there are two different shapes to choose from, TRIANGLES or RECTANGLES. You choose betweend the different shapes by clicking on the CHANGE-CREATE-MODE button. The button changes between a point, a triangle and a rectangle, for the different modes and shapes. Note that rectangles are not exactly rectangles, but more four-sided polygons, since the corners aren't dependent of each other. There is a very big difference between triangles and 'rectangles'. Since a polygon really is a two-dimensional thing, every point in the polygon must lie on a plane i three dimensions. -10- This is no problem with triangles, since a plane can be defined with just three points, and however the corners in the triangle is located, the triangle is always an twodimensional plane. However, with an four-sided polyon, the corners can be defined so that the polygon is no longer 2dimensional but 3dimensional. This means that from som e angles, the polygon might behave strange, will not be seen etc. This problem is easily solved with splitting the rectangle into two triangles. If this doesn't make sense to you, don't worry. You'll understand what I mean when the problem occur. NO BACKFACE-CLOCKWISE ORDER When you create a polygon, the AS that define the polygon, must be in clockwise order from the viewer. Why is that? Well, thats needed because 3dedit and the 3dengine on which the program is built must now which side is fron and which side is back. Most faces (or polygons) in an object has only one side that its visible. If you think of a solid box, each rectangle that the box is 'made' of has only one side that's visible. EXAMPLE: If you have created three points 1 2 3 2 1 3 would be visible from the viewer but 1 3 1 2 2 3 would not be visible. You'll probably get it. BACK-FACE POLYGONS To create polygons that has a backface, in other words, like a sail or a wing, a polygon thats always visible, despite angle, you should turn the BACK-FACE-MODE on. This is done by pressing the BACK-FACE-MODE button. DESTROYING A POLYGON Just click on the DESTRYO-button and make sure that the CREATE-MODE is set to the shape you're about to destroy. The AS should be located at the points that define the polygon. Sometimes you have created more than one polygon at the same points. Then the polygon that was first created is destroyed first. -11- -THE PANEL AND THE BUTTONS- +---------------------------------------------------------+ |<-22 (COLORS) 23 ->| |---------------------------------------------------------| |+---+ +---+ +---+ +--++--++--++--++-----+--++--++--+| || | | | | | |9 ||10||11||12||REFLECT ||15||16|| || 1 | | 2 | | 3 | +--++--++--++--++--------++--++--+| |+---+ +---+ +---+ +-----------+ +--++--+| | X Y Z | CREATE 13 | |17||18|| | +-----------+ +--++--+| |+---+ +---+ +---+ +--+ +-----------++--------++--++--+| || | | | | | |7 | |DESTROY 14 ||SMOOTH ||19||20|| || 4 | | 5 | | 6 | | | +-----------++--------++--++--+| |+---+ +---+ +---+ +--+ +------+| | |Free21|| | +------+| +---------------------------------------------------------+ 1. Move-button X. This button moves the active AS along the x-axis. Use both mouse buttons. 2. Move-button Y. This button moves the active AS along the y-axis. Use both mouse buttons. 3. Move-button Z. This button moves the active AS along the z-axis. Use both mouse buttons. 4. Rotate-button X. This button rotates the object about the x-axis. Use this button only in FREE-VIEW-MODE. Use Both mouse-buttons. 5. Rotate-button Y. This button rotates the object about the y-axis. Use this button only in FREE-VIEW-MODE. Use Both mouse-buttons. 6. Rotate-button Z. This button rotates the object about the z-axis. Use this button only in FREE-VIEW-MODE. Use Both mouse-buttons. 7. Change to object-move-mode/AS-move-mode. In object-move-mode, the move-buttons makes the whole -12- object move instead of just the active AS. In AS-move-mode,just the active AS moves. When the object-move mode is enabled, the button has a 3dbox shape in it, else it is just a dot. 9. CHANGE SORTMODE. When an object is displayed, all visible polygons are sorted on the distance from the viewer. There are three different distances, nearest-distance, farthest distance and average distance. For each polygon created you must have selected an appropireate sort-mode. If you have choosen the wrong sort-mode, the object may look strange in some angles. 10. BACK-FACE MODE. Often a polygon has a side thats always invisible. By changing the backface-mode, you can select between polygons thats always visible and polygons with just one visible side. A side of a cube is a typical polygon with just one visible side, but for an example a sail would have to visible sides. 11. SEE POINTS.Switch between seeing every point that an object is made of, and not to see them. Have the points seen make design a lot easier. 12. Create-mode. By clicking this icon, you can change what to create with the 'CREATE'-button and what to destroy with the 'DESTROY'-button. You can change between points, triangles and rectangles ( not exactly rectangles, but a foursided polygon anyhow). Points can't be destroyed at this time. 13. Create-button. With this button you create a new point/ triangle/ rectangle depending on which create-mode you have selected. Note that when you create points, a new point will be created for each AS thats activated. 15. View X-Y 1. Watch the object from the front. 16. View X-Y 2. Watch the object from the behind. 17. View X-Z 1. Watch the object from the above. 18. View X-Z 2. Watch the object from the below. 19. View Y-Z 1. Watch the object from the left side. 20. View Y-Z 2. Watch the object from the right side. 21. View free. Free-view where you can rotate the object into any angle. 22. Change next page of colors. 23. Click in this area to select a color. -13- KEYS ESC Quit Nump.1 Rotate object about Z-axis Nump 3 Rotate object about Z-axis Nump.4 Rotate object about Y-axis Nump 6 Rotate object about Y-axis Nump.7 Rotate object about X-axis Nump 9 Rotate object about X-axis Nump.1+CNTRL Move object along Z-axis Nump 3+CNTRL Move object along Z-axis Nump.4+CNTRL Move object along Y-axis Nump 6+CNTRL Move object along Y-axis Nump.7+CNTRL Move object along X-axis Nump 9+CNTRL Move object along X-axis LEGAL STUFF SOFTWARE LICENSE 3DEDIT Copyright 1993 HUMAN SOFTWARE Inc. All Rights Reserved You are free to use, copy and distribute 3DEDIT only for NONCOMMERCIAL use if: No fee is charged for use, copying or distribution. It is not modified in any way. Clubs and user groups may charge a nominal fee not to exceed (£3.00$) for expenses and handling while distributing 3DEDIT -14- HUMAN SOFTWARE hereby disclaims all warranties relating to this software, whether express or implied, including without limitation any implied warranties of merchantability or fitness for a particular purpose. HUMAN SOFTWARE will not be liable for any special, incidental, consequential, indirect or similar damages due to loss of data or any other reason, even if HUMAN SOFTWARE or an agent of 3DEDIT has been advised of the possibility of such damages. In no event shall HUMAN SOFTWARE's liability for any damages ever exceed the price paid for the license to use software, regardless of the form of the claim. The person using the software bears all risk as to the quality and performance of the software. -15-