# extrusion and matixes

This topic is 2534 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

## Recommended Posts

hello.
I'm still creating an impoerter for ifc
I have two beam and each beam have 2 points StartPoint and EndPoint and
two matrixes mxRotation1 and mxRotation2.

beam 1:
StartPoint = -7315.2 0.0 0.0

pmx(3x3matrix) = 0 0 1
0 1 0
1 0 0

pmxExtrude(3x3matrix) = 1 0 1
0 -1 0
0 0 1

m_vDirExtrusion = 0.0 0.0 0.1

beam 2:
StartPoint = 0.0 0.0 0.0

pmx(3x3matrix) = 0 0 1
0 1 0
1 0 0

pmxExtrude(3x3matrix) = 1 0 1
0 -1 0
0 0 1

m_vDirExtrusion = 0.0 0.0 0.1

Extrusion
StartPoint + *m_vDirExtrusion * m_dDepth ;

this is the correct result:

Beam1:

Coord.: x=-7315.2 y=0 mm z=0 mm
Coord.: x=0 mm y=0 mm z=0 mm

Beam2:

Coord.: x=0 y=0 mm z=0 mm
Coord.: x=7315.2 y=0 mm z=0 mm

But i don't know how i can manage the rotation matrixes.
1)if: i only trasform m_vDirExtrusion the result is correct but:
2)i'm not sure about what do the matrixes , i know only that

pmx(3x3matrix) is related to start position and
pmxExtrude(3x3matrix) is related to the extrusion
now:
I must understand what is the relation from matrixes and correct results for completelly understand
what are these matrixes.
this

1. 1
2. 2
3. 3
Rutin
15
4. 4
khawk
13
5. 5
frob
12

• 9
• 11
• 11
• 23
• 12
• ### Forum Statistics

• Total Topics
633662
• Total Posts
3013231
×