Getting the angle of the ground under the player

[raccoon2112]

I really suck with vectors. What I need to do is get the angle of the ground under the player, so that it returns 0 when the player is on flat ground and if the player is on a slope then the angle of the slope (preferably relative to the player, so that it returns a negative number when going down the slope)

[Wizard of Ass]

[lua]SurfaceAngle = util.Trace(LocalPlayer():GetPos(),Vector(0,0,-512),LocalPlayer()).Normal:Angle()[/lua]

[raccoon2112]

[lua]
local tr = util.QuickTrace(ply:GetPos(), Vector(0,0,-512), ply)
local groundang = tr.Normal:Angle()
[/lua]
just outputs 90, 0, 0

[editline]8th November 2010[/editline]

[QUOTE=thejjokerr;25937144]-snip-

What I tried to do was calculate a [b]2d angle[/b] using [b][url=http://wiki.garrysmod.com/?title=Math.cos]Math.cos [img_thumb]http://wiki.garrysmod.com/favicon.ico[/img_thumb][/url][/b] and Pythagoras.[/QUOTE]
That's what I need

[Loures]

Try this one:
[lua]
local tr = util.QuickTrace(ply:GetPos(), Vector(0,0,-512), ply)
local groundang = Angle(math.NormalizeAngle(tr.HitNormal:Angle().p), math.NormalizeAngle(tr.HitNormal:Angle().y), math.NormalizeAngle(tr.HitNormal:Angle().r))
[/lua]

[raccoon2112]

what have I done!!!

[lua]
local groundangw = (Angle(math.NormalizeAngle(tr.HitNormal:Angle().p) , math.NormalizeAngle(tr.HitNormal:Angle().y), math.NormalizeAngle(tr.HitNormal:Angle().r)) + Angle(0, math.NormalizeAngle(ply:EyeAngles().y), 0)) -- thanx Loures
local groundangl = ((math.abs(math.NormalizeAngle(groundangw.p))) - 90) * (math.abs((math.NormalizeAngle(groundangw.y)) / 180 * 2) - 1)
[/lua]

groundangl outputs the slope angle relative to where the player is facing, which is exactly what I wanted. It's really complicated but it works perfect, thanks for all of the help guys!.

[ralle105]

Assuming you have the variables eyeAngles and groundNormal
[lua]
eyeAngles.Pitch = 0
eyeAngles.Roll = 0
eyeAngles = eyeAngles:Forward()

local elevation = math.acos(eyeAngles:Dot(groundNormal))*180/math.pi-90
[/lua]
elevation is positive when going up a steep and negative when going down (stretching from 90 to -90)

Now go learn some vector math and you'll be able to solve these problems on your own:v:

[raccoon2112]

[QUOTE=ralle105;25939099]Assuming you have the variables eyeAngles and groundNormal
[lua]
eyeAngles.Pitch = 0
eyeAngles.Roll = 0
eyeAngles = eyeAngles:Forward()

local elevation = math.acos(eyeAngles:Dot(groundNormal))*180/math.pi-90
[/lua]
elevation is positive when going up a steep and negative when going down (stretching from 90 to -90)

Now go learn some vector math and you'll be able to solve these problems on your own:v:[/QUOTE]

[lua]
local tr = util.QuickTrace(self:GetPos(), Vector(0,0,-512), self)
local eyeAngles = Angle(0, self:EyeAngles(), 0):Forward()
local groundNormal = tr.HitNormal
local elevation = math.acos(eyeAngles:Dot(groundNormal))*180/math.pi-90
[/lua]
outputs 0 on 50% of slopes

[ralle105]

Take another look at your eyeAngles line.

[raccoon2112]

[lua]
local tr = util.QuickTrace(self:GetPos(), Vector(0,0,-512), self)
eyeAngles = self:EyeAngles()
eyeAngles.Pitch = 0
eyeAngles.Roll = 0
eyeAngles = eyeAngles:Forward()
groundNormal = tr.HitNormal
local elevation = math.acos(eyeAngles:Dot(groundNormal))*180/math.pi-90
[/lua]

fork year

[editline]8th November 2010[/editline]

[QUOTE=ralle105;25939813]Take another look at your eyeAngles line.[/QUOTE]

forgot the .y, I'm retarded

[raccoon2112]

I think this is what I'm going to stick with:
[lua]
local tr = util.QuickTrace(self:GetPos(), Vector(0,0,-512), self)
eyeAngles = self:GetVelocity():GetNormalized():Angle()
eyeAngles.Pitch = 0
eyeAngles.Roll = 0
eyeAngles = eyeAngles:Forward()
groundNormal = tr.HitNormal
local elevation = math.acos(eyeAngles:Dot(groundNormal))*180/math.pi-90
[/lua]