Basic concepts
MAGNET Modeler has two separate main modules: Modeler and Explorer. Modeler is used to create a virtual model (*.VM file) from a CAD drawing and other sources.
-
MAGNET Modeler supports the following for creation of the virtual model:
- Polylines
- Lines
- Points
- Blocks
- Splines
- Ellipses
- Arcs
- Circles
- If a map has 3D information, it is used based on the way each object type uses it.
In general, MAGNET Modeler does not use or require any specific units.
- Units are the same throughout the software, except for some features that work with meters (m).
- These include the walk mode and the speedometer.
- These features work correctly if the model has been created using the metric system (1 m = 1 unit).
Note that MAGNET Modeler does not correct errors in the source data.
- In many old maps, there are errors that may affect the virtual modeling.
-
The input data should consist of closed and continuous polylines.
- For example, crossing polylines and gaps in polylines cause problems when modeling buildings or material areas, but they work well when modeling fences or element chains.
Terrain model
- Terrain model is a surface that can be read from any grid, triangular network, or mesh that is in an AutoCAD drawing as 3D face elements.
-
All other MAGNET Modeler objects are modeled on top of the terrain unless otherwise defined.
- This is the basis for the whole model.
- If there is no terrain model defined, a flat terrain covering all the map elements is generated.
Surface
- A surface is a set of 3D surface elements with materials attached.
-
It can be generated from various surface objects, such as:
- Surface models
- Road models
- Material areas
- Roadlines
- Ditches
- Each surface object has specific material, texturing, and input geometry options.
Objects
-
Objects are 3D models such as:
- Buildings
- Fences
- 3D meshes and texts that have complex geometry or special texturing modes may contain multiple materials.
- Objects are generated from complex input data like polylines, texts, or 3D surfaces.
Elements
- Elements are texture elements or 3D surface elements that are defined by an insertion point (x,y,z), rotation angle, and scale.
- Elements can be generated from single positions (points, blocks) along a polyline as element chains or filled inside closed polylines as element areas.
- Forest objects also generate elements.
Glossary of special terms
- Alpha Channel: A black and white image that tells which parts of the image are transparent. Black areas are completely transparent, whereas white areas are totally opaque. Shades of gray describe partial transparency.
- Ambient: Surface color where no direct light is hit; also called shadow side color.
- Block: A group of objects. A block can contain any number of objects. A block is processed as one object.
- D Face/Face: Surface between three vertices. Faces are also called triangles.
- Dialog box/window: A window to which the user is supposed to react.
- Diffuse: Surface color where direct light hits. This is the most dominant color.
- Drawing units: The base units used in the AutoCAD drawing; usually meters.
- Emission: Color that is multiplied with other colors. Generally 0,0,0 but can be used to make a fluorescent effect.
- Frame rate: Number of frames (pictures) per second (FPS).
- Gouraud: A type of OpenGL shading.
- Grid: An even pattern of elements (points, etc.) that forms a square shape.
- Interpolation: In MAGNET Modeler, interpolation means attaching elements automatically on the surface of a certain object, usually on the ground.
- Material: Material of an element. Material defines the characteristics of the surface of the element. For example, texture and transparency are defined as a material.
- Mesh: An object consisting of 3D faces.
- OpenGL: The industry's most widely used and supported 2D and 3D graphics application programming interface (API).
- Orthophoto: A photo taken perpendicularly to the object; usually an aerial photo or satellite photo.
- Polyline: A line with two or more vertices.
- Rendering: Creating a 2-dimensional image or set of images (for moving pictures) of the 3-dimensional model from a specified view point.
- Shading: Processing the effects of light.
- Shininess: Scope of the reflection of the light source.
- Specular: Intensity and color of the reflection of the light source.
- Surface model/Terrain model: A 3D terrain which consists of 3D faces.
- Texboard: A billboard-like object in the model that has a certain texture assigned to it. It can be rotating, that is, it always faces toward the viewer. This is useful for modeling 3D objects such as trees. A texboard may also have partially transparent texture, which is useful for modeling non-rectangular objects, such as traffic signs.
- Texture: A picture used on the surface of a 3D object.
- Texturing: The way of placing texture on the surface of a 3D object.
- Tooltip: A small box of information appearing when the cursor is placed on top of a certain object.
- Triangle: A surface between three vertices. Triangles are also called 3D faces or faces.
- Vertex: A specific point in 3D space. Vertex is the corner point of a polyline, 3D face, or other 3D element.
- Topic: A point in space from which the view is seen.
- Viewport: A window or area with a certain view.
- Wireframe: A rendering process which shows only all edges.
- VRML: Virtual Reality Modeling Language. Industry-standard language for 3D in web.