Making a math function plot

[FAU78]

Hi. I am wondering if there are ways to plotting those mathematical functions... For example, y=ax+b, player's can set a and b by vgui and the shape of this function then is plotted somewhere in the game. (Of course the same vgui is the best).

Of course I can plot them by excel or other software, the question is how to upload those .vtf or .vmt file dynamically in the game.

Have any idea? Thanks!

[MakeR]

You could plot the functions yourself using the [url=http://wiki.garrysmod.com/?title=Draw]draw library[/url], you just need to loop through the x axis, say from -10 to 10 and calculate the y value, then you can either draw a line from the last value to this one, or just draw a point.

[FAU78]

Thanks.. Partly understand...

[Crazy Quebec]

Completely untested but it should work :
[lua]local function Y(x,a,b)
return a*x+b
end

local a = 3 -- Default values for the example
local b = 5

local xMin = -10 -- Lowest value to draw
local xMax = 10 -- Highest value to draw
local step = 1 --The distance between points on the x axis.

local baseX = ScrW() * 0.5 -- This is the middle of the screen
local baseY = ScrH() * 0.5 -- This is the middle of the screen

hook.Add("HUDPaint", "DrawFunction", function()

if (xMin >= xMax) or (step > xMax - xMin) then return end -- Checking our values

for x1 = xMin,xMax-1,step do

local x2 = x1+step -- Calculating the next value of x so we can draw a line between the 2
local y1 = Y(x1,a,b)
local y2 = Y(x2,a,b)

print("("..x1..", "..y1..") to ("..x2..", "..y2..")") -- For debug purposes

surface.DrawLine( baseX + x1, baseY + (y1*-1),baseX + x2, baseY + (y2*-1) ) -- Adding our points to the coordinates of the middle of the screen. I'm reverting the y because I'm pretty sure that on the screen a lower y is higher. I could be wrong.

end

end)[/lua]
:science:

[Cubar]

[QUOTE=Crazy Quebec;20919053]Completely untested but it should work :
[lua]local function Y(x,a,b)
return a*x+b
end

local a = 3 -- Default values for the example
local b = 5

local xMin = -10 -- Lowest value to draw
local xMax = 10 -- Highest value to draw
local step = 1 --The distance between points on the x axis.

local baseX = ScrW() * 0.5 -- This is the middle of the screen
local baseY = ScrH() * 0.5 -- This is the middle of the screen

hook.Add("HUDPaint", "DrawFunction", function()

if (xMin >= xMax) or (step > xMax - xMin) then return end -- Checking our values

for x1 = xMin,xMax-1,step do

local x2 = x1+step -- Calculating the next value of x so we can draw a line between the 2
local y1 = Y(x1,a,b)
local y2 = Y(x2,a,b)

print("("..x1..", "..y1..") to ("..x2..", "..y2..")") -- For debug purposes

surface.DrawLine( baseX + x1, baseY + (y1*-1),baseX + x2, baseY + (y2*-1) ) -- Adding our points to the coordinates of the middle of the screen. I'm reverting the y because I'm pretty sure that on the screen a lower y is higher. I could be wrong.

end

end)[/lua]
:science:[/QUOTE]

Wow, nice.

[FAU78]

Wow... Really appreciate!

[FAU78]

Another problem is the hook. I find that if I do not use
[lua]
hook.Add("HUDPaint", "DrawFunction", function()
[/lua]
but directly put the surface.DrawLine in a function that mainly describe vgui, there will be no line drew. However, if I use this hook, it will draw at the beginning of the game, which is not what I want.

SO must surface.DrawLine relates to the "HUDPaint" hook or is there anyway that not let "HUDPaint" happen...

THanks

[Crazy Quebec]

It doesn't really matter where as long as it's in a drawing hook. In your case you should create a derma vgui and do the drawing in one of the panel's Paint hook.

[url]http://wiki.garrysmod.com/?title=DPanel[/url]
[url]http://wiki.garrysmod.com/?title=Vgui.Create[/url]
[b][url=wiki.garrysmod.com/?title=Panel.Paint]Panel.Paint [img]http://wiki.garrysmod.com/favicon.ico[/img][/url][/b]

[editline]02:13PM[/editline]

So that means that when defining your panel you want to draw on you can do this :
[lua]function mypanel:Paint()

if (xMin >= xMax) or (step > xMax - xMin) then return end -- Checking our values

for x1 = xMin,xMax-1,step do

local x2 = x1+step -- Calculating the next value of x so we can draw a line between the 2
local y1 = Y(x1,a,b)
local y2 = Y(x2,a,b)

print("("..x1..", "..y1..") to ("..x2..", "..y2..")") -- For debug purposes

surface.DrawLine( baseX + x1, baseY + (y1*-1),baseX + x2, baseY + (y2*-1) ) -- Adding our points to the coordinates of the middle of the screen. I'm reverting the y because I'm pretty sure that on the screen a lower y is higher. I could be wrong.

end

end[/lua]

And then you can change the a and b values through other derma controls. Also baseX and baseY's values should be the center of the control you want to draw on.

[MakeR]

I made this

[img_thumb]http://i44.tinypic.com/2itos5e.jpg[/img_thumb]
[img_thumb]http://i44.tinypic.com/357r3bn.jpg[/img_thumb]

Is it similar to what you are looking for?

[editline]06:31PM[/editline]

Click on the images, the line are a bit thin to see in the thumb.

[Crazy Quebec]

Looks quite like it, what do you use to draw points? surface.DrawLine(x1,y1,x1,y1) ?

[MakeR]

I'm actually using surface.DrawRect(x1 - 1, y1 - 1, 3, 3).

[editline]06:39PM[/editline]

In those images though I was using surface.DrawRect(x1, y1, 1, 1), but I changed it when I realised that this is wrong.

[FAU78]

[QUOTE=MakeR;20939152]I made this

[img_thumb]http://i44.tinypic.com/2itos5e.jpg[/img_thumb]
[img_thumb]http://i44.tinypic.com/357r3bn.jpg[/img_thumb]

Is it similar to what you are looking for?

[editline]06:31PM[/editline]

Click on the images, the line are a bit thin to see in the thumb.[/QUOTE]

Almost exactly what I want.

This is my code that define a vgui which belongs to the entity. I paste an example draw circle script inside.

[lua]
function ENT:PanelSetting()
local Frames=vgui.Create("DFrame")
Frames:SetPos(50,50)
Frames:SetSize(450,450)
Frames:SetVisible( true )
Frames:SetDraggable( true ) -- Draggable by mouse?
Frames:ShowCloseButton(true)

local NumSlide=vgui.Create("DNumSlider",Frames)
NumSlide:SetPos(25,25)
NumSlide:SetSize(100,40)
NumSlide:SetMax(24)
NumSlide:SetMin(0)
NumSlide:SetDecimals(0)

--Here is the part to drawing
local center = Vector( ScrW() / 2, ScrH() / 2, 0 )
local scale = Vector( 100, 100, 0 )
local segmentdist = 360 / ( 2 * math.pi * math.max( scale.x, scale.y ) / 2 )
surface.SetDrawColor( 255, 0, 0, 255 )
Msg("Hi Drawing")

for a = 0, 360 - segmentdist, segmentdist do
surface.DrawLine( center.x + math.cos( math.rad( a ) ) * scale.x, center.y - math.sin( math.rad( a ) ) * scale.y, center.x + math.cos( math.rad( a + segmentdist ) ) * scale.x, center.y - math.sin( math.rad( a + segmentdist ) ) * scale.y )
end
--Drawing the circle ends here

local Button=vgui.Create("DButton",Frames)
Button:SetPos(25,95)
Button:SetSize(50,50)
Button:SetText("OK")
Button.DoClick=function()
self.Fre=NumSlide:GetValue()
Frames:Close()
end
end
[/lua]

And this is the result:
[IMG]http://i43.tinypic.com/212bk08.jpg[/IMG]

No circle is put.

However, if I did it like this way:
[lua]
function ENT:PanelSetting()
...
end

hook.Add( "HUDPaint", "Circle", function()
local center = Vector( ScrW() / 2, ScrH() / 2, 0 )
local scale = Vector( 100, 100, 0 )
local segmentdist = 360 / ( 2 * math.pi * math.max( scale.x, scale.y ) / 2 )
surface.SetDrawColor( 255, 0, 0, 255 )

for a = 0, 360 - segmentdist, segmentdist do
surface.DrawLine( center.x + math.cos( math.rad( a ) ) * scale.x, center.y - math.sin( math.rad( a ) ) * scale.y, center.x + math.cos( math.rad( a + segmentdist ) ) * scale.x, center.y - math.sin( math.rad( a + segmentdist ) ) * scale.y )
end
end)
[/lua]

There will be a circle that drawing on the screen when the game start.

[IMG]http://i40.tinypic.com/2iswq3l.jpg[/IMG]

[Crazy Quebec]

2 things, you're not doing the drawing in your frame's Paint hook and you're using the middle of the screen as a center value. You should be using a value that will make it fit on said frame. If you just want it to draw in the center anyway you could put a condition to the drawing.

[FAU78]

I want to let it to be on the vgui panel, looks same as makeR does. However, when I use:
[lua]
local Frames=vgui.Create("DFrame")
Frames:SetPos(50,50)
Frames:SetSize(450,450)
Frames:SetVisible( true )
Frames:SetDraggable( true ) -- Draggable by mouse?
Frames:ShowCloseButton(true)
Frames.Paint=function(
for a = 0, 360 - segmentdist, segmentdist do
surface.DrawLine( center.x + math.cos( math.rad( a ) ) * scale.x, center.y - math.sin( math.rad( a ) ) * scale.y, center.x + math.cos( math.rad( a + segmentdist ) ) * scale.x, center.y - math.sin( math.rad( a + segmentdist ) ) * scale.y )
end
)
[/lua]
The nightmare was that the frame will even not come out...

Really Thanks....

[Crazy Quebec]

[lua] Frames.Paint=function(
for a = 0, 360 - segmentdist, segmentdist do
surface.DrawLine( center.x + math.cos( math.rad( a ) ) * scale.x, center.y - math.sin( math.rad( a ) ) * scale.y, center.x + math.cos( math.rad( a + segmentdist ) ) * scale.x, center.y - math.sin( math.rad( a + segmentdist ) ) * scale.y )
end
)[/lua]

That's because you put all of your code in the argument to the function and did not end it. :smile:

This should work better :
[lua]Frames.Paint=function()
for a = 0, 360 - segmentdist, segmentdist do
surface.DrawLine( center.x + math.cos( math.rad( a ) ) * scale.x, center.y - math.sin( math.rad( a ) ) * scale.y, center.x + math.cos( math.rad( a + segmentdist ) ) * scale.x, center.y - math.sin( math.rad( a + segmentdist ) ) * scale.y )
end
end[/lua]

[FAU78]

Er...................
Sorry........
In my script I did so... with the end on it...

[Crazy Quebec]

The important part is the parenthesis after function. You put all of the code in them while rhey should be closed.

[FAU78]

Er... Seems not this problem... Thank you guys very much.