OrcaFlex Manual - Orcina

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User Interface, 3D Views
a line in the view direction (defined by the view azimuth and view elevation) at a distance of view size * 1.5 from the
view centre. It is possible to rotate the view around both the view centre and around the viewer position.
Video export
Just as for wire frame views OrcaFlex can export video files of a replays in shaded views. When producing videos it
is very important to use compression, otherwise the video file size becomes unreasonably large. The software that
performs this compression is called a codec.
For wire frame replays OrcaFlex uses a built-in codec called run-length encoding. This codec is not suitable for
shaded replays and in fact there is no suitable built-in codec in Windows. We would recommend using an MPEG-4
codec of which many are available. In our experience the freely available XVID codec performs very well. The XVID
codec can be downloaded from www.orcina.com/Support/ShadedGraphics.
Should you wish to use a different codec you can select this from the Preferences form.
Hardware Requirements
The shaded graphics mode does require the presence of a DirectX 9 compatible graphics card. In our experience the
most important factor to consider when choosing a card to work with shaded graphics is the amount of memory. We
would recommend using a card with 256MB or more.
It is also important to make sure that your computer's graphics settings specify a colour mode of 16 bits (65536
colours) or better.
Notes: If your machine's graphics capabilities are insufficient then the shaded graphics mode may fail to
function properly or indeed fail to function at all. For example, low quality, blocky images usually
indicate a graphics card with insufficient memory. This problem can also manifest itself by failure
to draw the sky which appears plain white.
3.6.5 How Objects are Drawn
For best results you should centre your model close to the global origin. The Move Selected Objects
facility can help you do this.
Each object in the model is drawn as a series of lines using the Pen Colour, Line Width and Style (solid, dashed etc.)
defined in the drawing data for that object. You can change the pen colours etc. used at any time by editing the
drawing data for that object. To change the pen colour, select and CLICK the colour button on the data form and then
CLICK on the new colour wanted.
You can also exclude (or include) individual objects from the 3D view, by opening the model browser, selecting the
object and then using the Hide (or Show) command on the browser's Edit or pop-up menu.
Notes: In Windows, a line width of zero does not mean "don't draw" – it means draw with the minimum
line width. To suppress drawing either set the line style to null (the blank style at the bottom of the
drop down list) or else hide the object.
Wire Frame Drawing
On some machines the display driver cannot draw the dashed or dotted pen styles and instead
draws nothing. So on such machines only the solid and blank pen styles work.
For wire frame views the various objects are drawn as follows:
� The various coordinate systems can be drawn as small triplets of lines showing their origin and the orientation
of their axes. The wave, current and wind directions can be drawn as arrows in the top right hand corner of 3D
views. You can control both what is drawn (see 3D View Drawing Preferences) and the drawing data used.
� The Seabed is drawn as a grid using the seabed pen.
� The Sea Surface is drawn as a grid or as a single line. This is controlled by the user's choice of Surface Type as
specified on the drawing page on the Environment data form. If the Surface Type is set to Single Line then one
line is drawn, aligned in the wave direction. If the Surface Type is set to Grid then a grid of lines is drawn. This
line or grid is drawn using the sea surface pen.
� Shapes are drawn either as wire frames (Blocks, Cylinders and Curved Plates) or as a grid (Planes). As well as
controlling the pen colour, width and style, for shapes you can also control the number of lines used to draw the
shape.