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<< Click to Display Table of Contents >> Navigation: Albion 6 CAD User Guide > Drawing > Properties and Texture > Common Properties |
The common entity properties can be described as following.
Every entity has a colour. For circles, it is the colour of their outline, for lines it is their colour, and for polygons it is the colour of their outline, etc.
Colours in Albion can either be indexed, in which case they refer to the 256 colour standard AutoCAD palette, or they can be RGB or RGBA values (Red, Green, Blue, Alpha). RGB values are not limited to the 256 colours defined in the palette, but can be any of the 16.7 million colours available on a 24-bit display. RGBA colours are identical to RGB colours in range, the difference being that they have an Alpha or Transparency value too. The alpha value is not always supported, such as for text items (text is always 100% opaque). In such cases, the alpha value is ignored and is assumed to be 100% opaque. Also, certain older printers and older versions of Adobe Acrobat do not fully support RGBA colours. When a drawing with RGB or RGBA colours is saved as a pre-2004 DWG, then the closest matching colour from the AutoCAD palette is used in the DWG file.
Brushes are used to fill objects. The only native Albion objects that may be filled are circles and polygons. A brush can either be a solid colour (including RGBA colours), or a texture. Texture brushes are similar to traditional CAD hatches, except that they are entirely bitmap based. Any bitmap smaller than or equal to 1024x1024 pixels can be used as a texture brush. The scale of brushes is global throughout a drawing. Thus, their scale cannot be changed according to the entity that they are currently used on. Changing the scale and rotation of a texture brush will cause all objects referencing that texture to have their appearance changed.
Most entities support custom line types. These line types, such as dash or dot, cause the appearance of the line to be broken in places. Standard AutoCAD .LIN linetype files can be loaded with the LOADLIN command. Linetypes in Albion work slightly differently to AutoCAD and can thus cause inconsistencies, especially with more complex linetypes.
Proper Complex Linetypes, such as symbol linetypes are not supported.
Note that Albion has its own line type file format (.sclin). If possible, it is better to use this format than the AutoCAD compatible .LIN.
A Line Type is always paired to a Line Width. The line width defines the thickness of the line drawn, be it for a polyline, polygon, or circle. Polygons and polylines do not support unique line widths for each vertex. Scaling of line widths as entities are scaled is optional, and is controlled with the drawing variable s_scale_linewidths. If it is non-zero, then linewidths are scaled with entities. If 0, then they are not.
Line widths come in two variants: World widths and Point widths. A Point is a unit of measure that is 1/72 of an inch. Point line widths are useful because their width on paper is always the same, regardless of the viewport zoom on the object. World line widths behave like any other quanity in world space.
By Layer, By Block
All of the above properties except for Brush can be set to By Layer or By Block. This means that the entity gets this property from its layer or if it is part of a block, it gets the property value from the block insert.