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Combining Demos - Possible or Not?

the thread that Grazza linked tells all.
the vector generates the speed as it does in Quake. the polar coordinate system that DOOM uses allows for angled movement to be faster than straight movement.
the deception is that with SR40 and SR50 you aren't actually moving at an angle. You are telling DOOM to calculate the vector as if you were moving at an angle.
although the speed varies, I'd like to have a mathematical answer to the speed that wall-running gives. :)

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Let me clarify some of the details here.

Grazza already gave the details on the math involved here, that is, the strafing value in LMPC is the sideways input and the forward/backward value is the forward/backward input. While straferunning these are combined the way Grazza described it, so strafe40+GF50 becomes 10*sqrt(41) ~64 at the angle of arctan(0.8) ~ 38.66 degrees and strafe40+GF50 becomes 10*sqrt(50) ~ 70.7 at 45 degrees. See the Pythagorean Theorem for details :)

Note that these are still input values, they cannot be directly translated to speed as there are various other factors such as friction. We can't simply state that strafe40 running is ~28% faster than normal running or strafe50 running is ~10% faster than strafe40 running because the physics is complicated. However, in a straight line when the player doesn't get touched by any objects except the ground, it is true that the top speeds achieved are proportional to the input values (50, ~64 and ~71).

So the values 40 and 50 have nothing to do with the angle the running's at (see above), nor the units covered per second (which are much higher as Fredrik hinted, actually by simple forward top speed running you cover about 580 units/sec.)

There is some misunderstanding about the terms strafe40 and strafe50 here. Normally, strafe40 means sideways movement only (which is represented in LMPC as SR40 and SL40), strafe50 likewise. strafe40+forward (or backward) is what we call straferunning, in this case strafe40 running. Sometimes that gets abbreviated to SR40 running which is a bit confusing as SR40 in LMPC only refers to strafe right. Or even worse, the "running" is omitted and SR40 itself is referred to "strafe40 running" which is even more confusing. With the LMPC naming, strafe40 running can be GF50/GB50 + SL40/SR40 and strafe50 running can be GF50/GB50 + SL50/SR50.

As for wallrunning, I believe the reason behind it is still unknown. My tests show that when achieving the top speed, wallrunning is exactly twice as fast as normal running. More precisely, strafe40 wallrunning is twice as fast as strafe40 running and strafe50 wallrunning is twice as fast as strafe50 running. Surely there is some reason behind this as well...

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