In this part of the tutorial, you will learn how to set up cameras to render objects in different perspectives.
To begin, create a 3D object. This time I'm going to create a spiral.
Click on the spiral button on the 3D construction toolbar. A dialog box will appear and prompt you to give some info. The first item you look at is what direction the spiral is turning. Choose 1 or 2. In this instance it really doesn't matter what way it's turning. (This is just practice to familiarize you with usage of the program. When you decide that you are familiar with bCAD enough to start your own creations, then you decide which way you need a spiral to turn within your project.) What we are concerned with is the number of turns. The default is 2 turns. I suggest that you change that to 4 turns to really get an effect of a spiral. Lastly, you need to decide the number longitudinal and latitudinal lines to create the mesh. As with the sphere, the larger the number, the smoother the surface will be. However, once again, the larger the number, the longer to render.) I suggest that you set it between 15 - 25. Now click OK.
You're perpendicular intersecting lines (let's say crosshairs) appear. That's your prompt to place the crosshairs where you want the object to be (the Spiral Center). As you can remember with the construction of the sphere from Part One, how big you create this is not exactly how big it will be rendered. This time, however, size isn't really going to be an issue, because the camera we will create can render the object larger or smaller. Anyway, center the crosshairs and left click. Now you are prompted to give the Spiral Step. That's the distance between each turn's center point. Move to what looks like about an inch. You will notice that a white line is created and stretched as you move the mouse. This line will give you an idea of what the distance will be. If your line on the crosshairs has disappeared the distance you have moved, that means that you have followed a path straight from the center point at 0, 90, 180, or 270 degrees. If you were to move at an angle other than 0, 90, 180, or 270 degrees, you would notice that the line turns white. This is an indicator that your spiral will be exactly straight, and if it's not and you want it to be, just move the mouse aroung until the line is missing the distance you have moved or is at 0, 90, 180, 270 degrees. (You can play with the angular differences later, but for now, let's move the mouse to the left about an inch at 0 degrees or where you are keeping the horizontal line to disappear the lenght of the Spiral Step.) Left click. You are now prompted to give the spiral radius. This is the distance between the inside surfaces of the spiral (lets call it the core.) At first, if you haven't moved the cursor at all, you will have a blank grid. As soon as you move the cursor, a white circle will appear and the crosshairs will be the cursor point. This is your indicator of how big the core will be. Move the cursor until the circle is about 1 inch in diameter. Then left click. You are now prompted to give the Tube Radius. This is how big the tube will be as it spirals. This radius should be smaller than the Spiral Radius (or core). If it is the same or larger, it will cause the core to be less that the 1 inch we chose, or cause it to have no core and overlap itself. Again you will see a circle and crosshairs appear if you move the cursor. Create the Tube Radius at about 1/2 an inch in diameter and left click. bCAD will then create a mesh of the spiral.
Next, as with the sphere in Part One, give the spiral a color or texture. (If you don't remember how, go back to Part One and review.)
Soon we will work on the camera, but we first need to talk about the viewpoint. This will be essential, when we render, that we are seeing the Front View of the spiral when placing the camera. On the Viewpoint Toolbar, select the Adjust 3D Veiwpoint button. (It is the one with the side view of an eye with two lines angling out from the center of the eye.) A dialog box will appear. You will notice a sphere with 4 arrows on it at the top left of the box. This is for moving the viewpoint at certain intervals between exact front, rear, left, right, top or bottom. Move to the bottom right of the dialog box. Here you will see the buttons for the exact front, rear, left, right, top or bottom. We need to choose the button indicating the Top. To find that button, look for the shaded part of the cube representation. (The Top View button will be the one with the shaded portion of the cube on top.) Left click that button. You will notice the X, Y and Z proportions will change on the rotate area of the dialog box. If you were at Front View those figures would have all been 0.000. Once you have clicked the Top View, the first figure will change to 90.000. You could type these figures in manually, but the ease of the program kind of does it for you by giving you the buttons to do so. Once you have chosen the Top View, click OK.
You may not see your spiral on the grid, but it is there, just not in the viewing area. Left click on the center of the grid and hold. Then move the mouse around until your spiral appears in the viewing area. (You may need to use the Scroll Bars at the left and bottom to move the viewing area until your spiral appears.) When your spiral is in the viewing area, you will see theat it doesn't look much different than the Front View. (The difference is that the ends of the spiral will look centered instead of towards the top.)
Move the spiral to the top of the veiwing area. Now select the New Camera button on the Studio Toolbar. You will see the crosshairs again. Move the crosshairs to the bottom of the viewing area centering the verticle crosshair on the spiral. Left click and you will be prompted to aim the camera at what you intend to use it on. Move the cursor to the exact middle of the spiral. (That is, centered from left to right/top to bottom.) Again you can follow the verticle crosshair and it will disappear the length from the camera to the center of the spiral. Left click when you are in position. This brings up a dialog box. You can name the camera (call it front view or something that pertains to it's position), but is just as easy to let the program's default of Camera01 be the name. The camera lens length can be adjusted by clicking on the Lens Length buttons or by typing it in. However, the program automatically selects a length for you according to how far you have chosen to put the camera. The defaults for Halo Size, Halo Brightness, and Aperature should be ok for now. (Later we will see the use of these settings.) Also, the Lens Angle default should be ok. (I will discuss the Camera Position, Camera Target, and Frames sections in a later part. These are used for animation.) The Keep Z box should also be checked. If it is not, click on it. Then click OK.
Your camera will appear on the grid, however this is not all you have to do with it. Return back to the Front View. You will notice that the camera is not exactly centered at this view as it was in the Top View. (That's the interesting thing about working in 3D...You must look at all angles to be sure everything is in it's place in all directions of view.) To move the camera into it's proper position in this view, click the Select button on the Standard Toolbar. It's an arrow that looks like a mouse cursor or pointer. That will bring up a dialog box for the selection of objects. The first area you need to look for is the way in which you will select. The Location Area of the dialog box is what you need to look at. The first selection type is by Point; the second is by encasing the whole object by a rectangle; the third is by encasing a part of the object in a rectangle; and lastly by drawing a line across the object. You want to choose the Point type for this instance. Since there are two objects, and we only want to select the camera, the Point type is the best to use. If the Point type of selection is not chosen, chose it now, then click OK. This will take you back to the grid and your cursor will be a square with a dot in the middle. Move it on top of a part of the camera, somewhere not within the spiral. Once selected, right click to get out of the selection mode. (If you have accidentally selected the spiral also, then click the Deselect button to the right of the select button. A similiar dialog box will appear. It should be set at the Point type deselection. Click OK. The square with the dot will appear. Move the cursor to a part of the spiral not within the camera and left click. It will deselect the spiral. Then right click to get out of the deslection mode.)
With the camera now selected, click the Move button on the Transformations Toolbar. (The reason for selecting the camera is so that you don't accidentally move both objects. If you were not to select the camera, the Move action would prompt you to select an object to move. You will learn it is easier to select only that which you wish to do an action to when you have all kinds of objects overlapping or too close together with complex drawings.) The crosshairs will appear and you will need to put the center of them on the center of the camera, then left click.
Placing the crosshairs dead center on the camera will allow you to eyeball the approximate center of the spiral, which is where you will place the camera for rendering. Once you've centered the camera on the spiral center, left click to place the camera. Then right click to deactivate the Move action. (Once you have clicked a button, if a dialog box does not appear, usually right clicking will deactivate once you have done the action. So to cut this tutorial down a bit, assume that when you have clicked on an action, when you're done, right click to deactivate if I don't specify otherwise.)
Now, you may notice that the outer borders of the camera don't encompass the whole object. From here, render the object by clicking the Render button on the Studio Toolbar. The Render dialog box appears. Where the viewpoint pulldown box is, click on the pulldown button and choose Camera01. Then check to see if a light source is chosen. If it is not, then chose a light source. Then click OK. The spiral will be rendered. Notice the entire spiral is not rendered? That's because the camera border did not encompass the whole spiral.
Click out of that rendering and go back to the grid. We can adjust the Lens Length to encompass the entire spiral...and we can do it in a number of ways. Choose the Adjust Camera button on the Properties Toolbar. It will bring up a square pointer, prompting you to choose the camera you want to adjust. Chose the camera and a Camera dialog box for Camera01 will appear. Adjust the Lens Length by clicking on the 35 button. The lower the Lens Length, the larger the border of the camera will be without changing the actual distance of the camera to the object. It just enables a wider viewing area. Once you have chosen the 35 Lens Length, click OK. It will change the size of the viewing area of the camera for us, and now encompasses all of the spiral. Once again render the spiral with the Camera01 setting, and now you can see all of the spiral. Close out of the rendering.
You have just completed setting up a camera in the Front View. You can "play" with setting up additional cameras at different angles to see what they do, but I am not going to go into all of that. It's just like setting up the Front View camera, but using left, right, top, bottom, etc. You can also "play" with setting up a camera on different objects, or mulitple objects. Most of the program works in a similiar fashion for each type of 3D object. If your object seems to be way too big or small when rendered then click HERE to find out how to adjust and move the camera to different locations and how to stretch the camera without using the Adjust Camera button.
CLICK HERE
to see some images of the spiral!
