Along the lines of my search to draw lines at angles, maybe a clean up on isle 4 is needed, but I had to ask.

If I correctly understand, then I am used to grid coordinates like

But graphics (Circle, oval, etcs) seem to use

Which is fine and dandy, its just a simple rotation of begginning point (every point of view MUST have an origin)

I also get that (Cos(angle), Sin(Angle)) should be the point on a circle around my start point (and quadrants sorta) but what I do not get, is when to use what formula relative to my start point.

(For example 0,0....but should hold true if finding a point 1 away from 0, 0)

30 and 60 are the same angle (as far as me figuring Cos, Sin for the point

Can anyone simplify my complete confusion on points as to use COS(degree) vs COS("Negative"-Degree) vs "Negative"-COS(Degree) confusion???

(aka, what function do I use for what quadrant????)

sorry its so hard for me to define, but maybe some of you math majors out there can clean up my aisle 4 problem??? :shhh:

If I correctly understand, then I am used to grid coordinates like

Code:

0 | 270---|---90 | 180

Code:

90 | 180---|---0 | 270

I also get that (Cos(angle), Sin(Angle)) should be the point on a circle around my start point (and quadrants sorta) but what I do not get, is when to use what formula relative to my start point.

(For example 0,0....but should hold true if finding a point 1 away from 0, 0)

Code:

0 30 90 60 | / | / |/ |/ 270---|---90 180---|---0 | | 180 270

Can anyone simplify my complete confusion on points as to use COS(degree) vs COS("Negative"-Degree) vs "Negative"-COS(Degree) confusion???

(aka, what function do I use for what quadrant????)

sorry its so hard for me to define, but maybe some of you math majors out there can clean up my aisle 4 problem??? :shhh:

Code:

Sample Degree \ Reference point \ | \ | Quad II \| Quad I ------------------------------------ Reference point Quad III | Quad IV |

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