5. Basics - 3D
5.1 Generating projections, Rendering
5.2 Point input in 3D
5.3 Entering basic 3D-elements
5.4 Unit
5.5 Editing in 3D
5.6 Material
5. Basics - 3D  
 


The structure of the 3D menu is different from that of the other function lists. One focus of this menu is checking the correctness of existing 3D-elements (walls and openings entered in the plan) using different projections, and correcting them if necessary. On top of that you can create 3D elements as basic 3D shapes and edit these as well. The projections in which you work are views consisting of grid lines. Four possible views, four isometries, and the plan can be viewed. Moreover, you can choose perspective views freely.

In the 3D menu you can also render perspectives and isometries with or without culled wires. Alternatively, you can use the POV-Ray module to create a photorealistic representation of the 3D data. To do so, CYCAS offers various functions that help you to create a scene which can be exported to the POV-Ray module. This not only contains the 3D data, it also contains camera settings, light sources, and materials in order to achieve the best scene design.

The basics of 3D input are designed as an extension to chapter 3. Basics. 3D and 2D input are actually quite similar. The most notable difference is the coordinate system. The coordinate system has an additional axis, the Z-axis. Therefore, the following text will concentrate on the differences between 2D and 3D editing.  


 
coordinate system 3d Coordinate system : The planar cartesian coordinate system is extended by a Z-axis. "Z" is responsible for the height of elements.
projections Projections : Choose the projections you want to work in. Nine different projections are available:
button Plan : the X, Y and Z axis are available.
button View : You can choose between four different views. Each view shows the elevation of the elements. For each view either the X or the Y axis is missing. The Z axis is equivalent to the height.
button Isometry : Choose the desired isometric display. The isometries are rectangular axonometric projections with a side aspect of 1:1:1 with the angle between the depth lines and the horizontal being 30 degrees. All three axes are available in the isometries.  

button Perspective : Activates the perspective view displayed as grid lines. The perspective shown depends on the active camera and its' position.

Snap-to : The views and isometries are 3-dimensional displays on a 2-dimensional media. The snap-to function of CYCAS recognizes corner points of 3D-elements. For this reason, you can only enter elements by snapping-to the corner points of existing elements in the isometries and views. When working on the plan, the points are projected into the X / Y plane and the Z coordinate is 0.00.  

Keyboard input : For each numerical input you must choose the direction in the coordinate system first. Working in the projections you also have the choice to control the directions intuitively using the arrow keys. E.g. in a view projection you can control the Z-axis with the arrow keys up or down. CYCAS adapts the control of the keys to the current projection you are working in. But, you can also use the "X", "Y" or "Z" -keys for controlling the directions in the coordinate system.

Angle input : Enter angles numerically. Angles are measured counter-clockwise. The rotation axis can be placed in the 3D space freely.


 
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5.1 Generating projections, Rendering  
 


Create views, isometries or perspectives of your 3D design:
CYCAS computes line graphics or photorealistic graphics. Line graphics may be a wireframe or a hidden line representation. These are 2D line graphics that can be stored on a layer of your choice for viewing, editing, and finally for printing.

Moreover, you may export perspective views of your 3D project to the CYCAS POV-Ray module. It animates POV-Ray to render a photorealistic graphics of your design.

isometry

 

  • Choose a perspective

    Create perspective views by positioning a camera. A camera is displayed in your scene giving you information on its' position, on the direction of view and information on the cameras' angle.


camera

Camera : Enter a camera by positioning an eye point and a target point. You may enter identical height information for both points. Doing this, you avoid the appearance of "plunging" vertical lines in your perspective views. Or, you assign different heights to the points. This is achieved using the "Z"-key after having specified the X- and the Y- coordinate of each point.

- A : Control the view angle of a camera. The default entry of the view angle is 60 degrees. Increasing this figure you will achieve a wide angle view of the scene. Decreasing the angle causes the effect of a zoom objective.

- Change : This function changes between your cameras quickly. The active camera which defines the perspective view is marked in the guide line color.  

  • Render

    If POV-Ray [TM of the POV-Ray team] is installed on your system, you can send output to this raytracer even while you are still working on the 3D elements.

    Create a virtual scene which can be exported to POV-Ray. A scene being exported consists of the 3D elements including the materials, the camera that defines the perspective, and the light sources which illuminate the scene.

    The Render -function offers you various possibilities to manipulate POV-Ray:


render Decide which command line (only on Linux) has to be used for calling POV-Ray.

Looking at the output options you decide whether you want to save the computed picture or not. In the former case, you need to select the file format and a file name.

Choose the desired resolution calculated in pixels and choose which quality POV-Ray should use for rendering.

Also, you may decide whether or not anti-aliasing is to be employed during rendering. This enhances the quality of the rendered image.

Optionally, you can add a background. Either use the "Color" option or activate the "Sky" option. If "Sky" is active, you can choose to have "Clouds" rendered in addition.
If you prefer not to have a background rendered, because you want to fit the rendered image into a realistic photo later on you should use the "Alpha-Rendering". Choose the option "Targa + Alpha" and save the image file with the extension ".tga".

 

light

  • Light dialog box : ?

    It is very important to get the best illumination of your scene for rendering. Therefore, CYCAS offers two types of light sources in order to get the optimum of illumination. The pointlight suits simulating a lamp, while the spotlight simulates a lightbeam. Moreover, you can assign various settings to the lights in the lights' dialog boxes. These settings can be added to the database by saving them.

    Size : Control the size of the light source. The size specifies a distance from the light source to the point where the brightness of the light shall be reduced to the half of the original value. This value is very theoretically, so simply experiment with this. Simulating a sun would be assigning the value "0". In this case, the brightness of the light will not be decreased at any distance. Simulating a lamp would e.g. mean to set this value at "2" meters.

    Type : Choose a pointlight or a spotlight. The pointlight is a spherical light and the spotlight simulates a shaft of light. The pointlight is marked with an X and its radius (size) in the drawing. The spotlight is displayed with three lines indicating the direction of the light and the angle of the dissemination.

    Angle : This value only effects spotlights. Here, you can arrange the cone angle of the light.

    Shadow : Decide whether the light shall cause a shadow or not. Notice that computing shadows affords more rendering time. A deactivated shadow of a light can may be used to design your rendered images as well.

    Color : Choose the desired color of the light.


 

Light : Set one or more lights. Depending on the type of light you position one or two points in 3D space. A pointlight needs one point to be entered only. A spotlight is arranged by entering two points, the light source point and the target point. Controlling the Z-coordinate of these points works in analogy to the way of entering camera points.

-Alter : The lights you activate will be altered by the settings of the lights' dialog box.


 

  • Line graphics

    Create and design the presentation of your projects. From the pre-arranged perspective views, but also from the views, or elevations you may have CYCAS render line graphics of your design.


Wireframe : Compute a wireframe representation of the current projection. Depending on which projection you have chosen in the 3D -menu, you can have it rendered into a 2D drawing. Once the drawing has been rendered, you can choose on which layer you want to store the result. Therefore, it can be viewed and edited in the plan projection.

Hidden : Renders a 2D drawing with hidden (culled) lines. This function works like Wireframe.


 
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5.2 Point input in 3D  
 

Every single point of a 3D element has three coordinates. Referring to the CYCAS point input procedure (see 3.1 Entering points) it offers you two ways of entering the Z coordinate:


In the plan and the isometries :

  • 1. Use the "Z"-key of the keyboard to enter the Z coordinate in the input line below the drawing area. Numerical input is done additively. Enter "Z+:" 2.00 and apply this by pressing the Enter key. You could edit the height again: this time e.g. "Z+:" -1.00 - the Z coordinate of that point will be at 1.00 now. Only when you have confirmed the point finally its position is set.
  • 2. Snap-to points of 3D elements. You may use such points as reference points - and move the new point in all three dimensions from there.
  • 3. Snap-to points of 3D elements that have a Z coordinate of 0.00 - CYCAS will ask you to enter the base and the height of the element numerically.

In the views :

  • Theoretically, you could enter 3D elements in the views just like you would in the plan and isometric projections. However, it can not be determined accurately at which depth a point that you snapped-to actually is. Still, working in the views is useful for editing elements. You may measure distances between two points and you may correct the heights assigned to the elements.


 
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5.3 Entering basic 3D elements  
 

The 3D elements that can be created are basic 3D elements such as polygons, prisms or tubes. All 3D elements can be altered in the different projections using the Edit function list. You can assign materials to those elements when entering them.

For entering basic 3D elements chapter 5. Basis - 3D is important, as it describes the use of the Z coordinate in the different projections. When working in the projections, you must be careful to snap-to the correct points in space.  
cuboid Cuboid : Enter a cuboid using two points. This cuboid is assigned a base and a height. Assign a Z coordinate to each of the two corner points of the cuboid, so that the points lie diagonally across from each other. If you do not enter a Z coordinate for the two corner points, you can enter the base and height numerically after having confirmed the second point.
 
sphere Sphere : A sphere is created in analogy to entering a circle. The center is positioned in the center of gravity of the sphere, whereby, the position and the Z-height are determined. The radius is defined by a point on the surface of the sphere.
 
polygon Polygon : A polygon describes an area. This area is assigned a base (=bottom). The base of the area is extracted from the first polygon point. If you do not assign a Z coordinate to the first polygon point, you can, after closing the polygon, enter the base on the input line numerically. (See 3.7 Polygons for more information on polygons).
 
prism Prism : A polygon describes an area. This area is assigned a base and a height. Entering the polygon and specifying the base are done just like you would for a polygon. After closing the polygon you have to enter a height for the prism. (See 3.7 Polygons)
 
tube Tube : Enter a tube. Place a center point and enter a radius. By specifying a base and a height you set the position of the tube in space. You can specify the base either by assigning a Z coordinate to the center point or by entering it numerically. Finally, you have to select the number of segments for the tube.
 
cone Cone : A cone is created in analogy to the tube. Set the middle point and the radius of the cone. Finally, you define the base and the hight of it.
 
cut-cone Cut-Cone : Enter this element as described for the cone. But you need to enter the top radius of the cutted cone additionally.
 

3d-line 3D Line : A 3-dimensional line in space. A start and an end point describe the position of the line. They have three coordinates each, one for the X, Y and Z directions.

Attach Wall : Extend walls up to a plane in space. Use this function to edit walls upwards in the Z-direction. Start by defining a plane in space to which you want to extend the wall. In an isometric view you specify 3 points of a plane. Then, select the wall elements that are to be attached to the plane specified. The selected walls will be extended upwards. Use this function to edit walls upwards to a bevel plane, e.g. of a roof.


 
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5.4 Unit  
 

isometry

The Unit function list contains special architectural elements. These units are elements such as a gable wall, a stair, or a round pillar. With these units you can create a 3D model of your design easily.
Assigning materials to these 3D units enables you to have 3D work rendered by passing the data on to shader or raytracing programs.  


  • Unit function list - input

    Expecting you have read the 3D basics at the beginning of this chapter, the paragraphs following will describe the units giving notes on their input.
    At the beginning of each function you enter the numerical values necessary in order to scale and position the elements correctly in space.


        
gable wall Gable wall : The gable wall element is a wall in which you can place openings. Specify the base for the gable wall first. Then, you have to enter the wall height and the gable height. You can place the gable wall in the plan by placing two corner points afterwards.

ceiling Ceiling : At the beginning you have to enter the base and height of the ceiling. Then, you can describe the ceiling area with a polygon.

beam Beam : First, enter the width of the beam. Then, enter the base and height of the element. After that, you can place the beam in the plan like you would for an axis wall.

pillar Pillar : Enter a rectangular pillar by specifying its width and thickness first. Then, set its position in space by entering a base and height for the element. After that, you can keep placing pillars until you abort the function.

round pillar Round Pillar : You can place round pillars by entering their radius first, then, their base and their height. After that, you can keep placing rounded pillars until you abort the function.

stairway Stairway : Enter a stairway. You specify a number of options for the stairway first. You need to enter, in order: the width, the step height, the nosing and finally the number of steps. What remains, are as usual the base and height. After that, you can place the stairway in the plan by placing two points, the first being the lower end, the second being the higher end of the stair. You can keep adding further stairs using the same settings.

profile Profile : This function allows you to place window profiles in openings easily. In the input line you have to specify the number of monials and transoms. After that, you need to select the opening in which the profile is to be placed. A profile consists of monials and transoms which are distributed evenly in the opening. A window pane is placed automatically in the profile and has the material "Glass" assigned to it automatically. You can change the material of the profile without altering that of the glass pane. Furthermore, you may adjust the frame size of the profile in the button below.


 
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5.5 Editing in 3D  
 

The Edit function list can be used for 2D and 3D elements. And, you can operate in the different projections easily. We would like to refer to chapter 4.11 Edit again, because you can use all of the functions mentioned there working in 3D. Therefore, the paragraphs following deal with the 3D edit functions which are used differently in comparison to the 2D-editing.

The Move function is mentioned to clarify how you may use the two ways for entering distances with respect to the Z coordinate. This approach applies to the function Copy, -Multi and Series as well.  

  • 1. Enter distances using directional and numerical input. Herewith, you can use of the "Z"-key for entering the Z coordinate of points. (See also 5. Basics - 3D, Keyboard input.)
  • 2. Enter distances by using two points in space.

Move points of 3D elements: This enables you to model 3D elements in all projections. Please bear in mind that while using the elevation and plan projections you can also (accidentally) activate points in the depth, as the points of 3D elements come to rest on top of each other in those projections.

Polar : You can create a polar series around the Z-axis. Example : Creation of spiral stairways. Enter a Z value in addition to the rotation angle.  

Rotate : Rotation in 3 dimensions. Two points determine the position of the rotation axis in space. Enter the rotation angle numerically.

Mirror : Mirroring in 3 dimensions. Three points determine the position of the mirror plane.

Stretch : Stretching elements in 3 dimensions. Either specify a factor for each of the three axes or snap-to two points that determine the factor as a distance in space.


 
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5.6 Material  
 


Creating materials within CYCAS is very useful for the direct output to a render program such as POV-Ray [TM of the POV-Ray team]. Furthermore, the material information of your 3D elements will be passed along when exporting to other 3D-packages.

For the creation of your materials in detail, you can use POV-Ray for getting a preview of each slight enhancement on your materials - in order to test the transparency, the color, the reflections, etc. before rendering.

  • Materials are textural information that is assigned to the 3D elements.
  • When outputting to a shader or raytracer, this information is passed along with the element data.
  • When creating 3D elements, the material in the current materials dialog box will be assigned to any newly created element.
  • Assigning materials to wall elements is done in the walls' dialog boxes.
  • 3D-Lines form an exception as they cannot possess a material.
  • Check the material assignment using the element information. To open this window you right-click on the respective element.

 

  • Material dialog box: ?

    The materials dialog boxes are accessible from the 3D and the Unit menus. Use these dialog boxes to assign colors and materials to 3D elements. Wall elements can have materials just like any other 3D element.


Name : Create your material database by assigning and saving names for your materials. Only materials which have been saved are taken into account when exporting data for rendering.

Color : Choose the desired material color and adjust the brightness of the material.

Transparency : Choose the transparency. A value of "0" disables this option.

Reflection : The higher this value, the stronger the material will reflect its surroundings.

Ambient : Arrange the luminosity of the material.

Highlight : Choose how "shiny" the material should be. The higher the value, the more polished the material will look.

Refraction : This is a toggle option (it can be turned on or off), the effects of this option are visible on transparent surfaces only.

Metallic : Choose whether the material should appear metallic or not.  

  • Texture : If you want to work with textures, CYCAS offers these possibilities for assembling graphics on 3D elements with POV-Ray.

Choose the type of texture and define the position of it.
Off : The textures are not available.
Default : If this type is set, CYCAS differs between wall elements and 3D elements. Textures will be mapped on walls lengthwise. But, the texture type "default" mappes textures on 3D elements in Z-direction, which means from above.
Spherical : The texture will be assembled spherically.
Cylindrical : The texture will be wrapped around the element cylindrically.
Planar X, Y, Z : This option causes the texture to be brought up on the element orthographically; depending on the axis chosen.
Image : Choose an image to create the texture.
Repeat : Toggle this option. Repeating a texture means that it will be copied infinite in all directions.
Size : Here, you can control the size of the texture.
Offset : Manipulate the offset of the texture. Offset the image from the origin (always lower left corner).

Preview : Test the material. In a separate window POV-Ray will render a sphere giving you a material preview.  


  • Alter - correcting materials

Change the material properties of walls or 3D elements. You need to choose a new material from your material database first. The function Alter activates the elements to which you want to assign the new material. Also, you can use this function, in case you have not yet assigned any materials.


 
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