tfc:334

# 3.3.4- DRAWING SECTION LINES

Section lines are used to a) point where a cross-section is taken, b) point in what direction it has been taken (towards entrace/towards-bottom), so we can identify left and rigth sides appropiately. They can form an L-shape which traverses passage. Long line joints cross-section with the place it was taken, and traverses passage but it's invisible while on passage. Thus short line is in the opposed side, and shows an arrow pointing direction used when cross-section was taken. In order to achieve this, some tricks are needed.

We could guess that we need to draw a straigth line, and we would be wrong. We need to draw a curve instead, so there will be control points that will allow set line sizes in order to get them out of passage.

Say you have a section point over a passage. You click below this point and drag until you reach passage wall. Then go to oposed side, click and drag until the other wall is reached. By dragging until walls are reached, you are placing control points next to walls, and both line parts will be draw accordingly on final pdf output. If you dragged into the passage, line parts will break into the passage.

Even if you drawed a curve, you'll get a straigth line between the two points you clicked in, and long line parts will be as long as you dragged the mouse.

To get the arrow, you need an option. Write in options textbox:

-direction end

This means that an arrow will be drawn on second (final) point. As previously explained obout lines, arrow will be draw on line's left side, as evidenced by the yellow tick on line's first point. So, to get a section line which points towards left, you need to draw first point lower than second one, and use “-direction begin” option so the arrow is drawn on first (initial) point. To get a section line wich points towards rigth, first point must be higher than second one, and you should use “-direction end” option.

• tfc/334.txt