<function name="BSplinePoint" parent="math" type="libraryfunc"> <description>Basic code for Bezier-Spline algorithm.</description> <realm>Shared and Menu</realm> <file line="144-L160">lua/includes/extensions/math.lua</file> <args> <arg name="tDiff" type="number">From 0 to 1, where alongside the spline the point will be.</arg> <arg name="tPoints" type="table">A table of <page>Vector</page>s. The amount cannot be less than 4.</arg> <arg name="tMax" type="number">Just leave this at 1.</arg> </args> <rets> <ret name="" type="Vector">Point on Bezier curve, related to tDiff.</ret> </rets> </function> <example> <description>Example usage of the function, makes a black box moving along the beizer curve made out of 4 points.</description> <code> local points = { Vector( 100, 100, 0 ), Vector( 200, 200, 0 ), Vector( 300, 100, 0 ), Vector( 400, 200, 0 ) } hook.Add( "HUDPaint", "BSplinePointExample", function() -- Draw the points for _, p in ipairs( points ) do draw.RoundedBox( 0, p.x - 2, p.y - 2, 4, 4, color_white ) end -- Draw the spline surface.SetDrawColor( 255, 0, 0, 255 ) local lastPos = math.BSplinePoint( 0, points, 1 ) for i=0, 10 do local pos = math.BSplinePoint( i / 10, points, 1 ) surface.DrawLine( lastPos.x, lastPos.y, pos.x, pos.y ) lastPos = pos end -- Draw a point on the spline local pos = math.BSplinePoint( ( math.cos( CurTime() ) + 1 ) / 2, points, 1 ) draw.RoundedBox( 0, pos.x - 2, pos.y - 2, 4, 4, color_black ) end ) </code> </example>⤶ ⤶ ⤶ <example>⤶ <description>Interactive demo</description>⤶ <code>⤶ ⤶ local PANEL = {}⤶ ⤶ PANEL.Init = function( panel )⤶ panel:SetText( "" )⤶ panel:SetSize( 24, 24 )⤶ panel.Dragging = false⤶ end⤶ PANEL.OnCursorMoved = function( panel, x, y )⤶ if ( panel.Dragging ) then⤶ local x, y = input.GetCursorPos()⤶ panel:SetPos( panel.StartPos.x + x - panel.CursorPos.x , panel.StartPos.y + y - panel.CursorPos.y )⤶ end⤶ end⤶ PANEL.OnMousePressed = function( panel, x, y )⤶ panel.Dragging = true⤶ local x, y = input.GetCursorPos()⤶ panel.CursorPos = { x = x, y = y }⤶ local x, y = panel:GetPos()⤶ panel.StartPos = { x = x, y = y }⤶ end⤶ ⤶ PANEL.OnMouseReleased = function( panel, x, y ) panel.Dragging = false end⤶ PANEL.OnCursorExited = PANEL.OnCursorMoved ⤶ ⤶ local MovableButton = vgui.RegisterTable( PANEL, "DButton" )⤶ ⤶ ⤶ local f = vgui.Create( "DFrame" )⤶ f:SetSize( 500, 500 )⤶ f:Center()⤶ f:MakePopup()⤶ ⤶ local oldPaint = f.Paint⤶ f.Paint = function( pnl, w, h )⤶ oldPaint( pnl, w, h )⤶ ⤶ local points = {}⤶ for k, pnl in ipairs( pnl:GetChildren() ) do⤶ local x, y = pnl:GetPos()⤶ if ( pnl.Dragging != nil ) then⤶ table.insert( points, Vector( x, y, 0 ) )⤶ pnl:SetText( #points )⤶ end⤶ end⤶ ⤶ surface.SetDrawColor( 255, 0, 0, 255 )⤶ local lastPos = math.BSplinePoint( 0, points, 1 )⤶ for i=0, 32 do⤶ local pos = math.BSplinePoint( i / 32, points, 1 )⤶ surface.DrawLine( lastPos.x, lastPos.y, pos.x, pos.y )⤶ lastPos = pos⤶ end⤶ end⤶ ⤶ vgui.CreateFromTable( MovableButton, f ):SetPos( 100, 100 )⤶ vgui.CreateFromTable( MovableButton, f ):SetPos( 200, 200 )⤶ vgui.CreateFromTable( MovableButton, f ):SetPos( 300, 100 )⤶ vgui.CreateFromTable( MovableButton, f ):SetPos( 400, 200 )⤶ ⤶ local addBtn = vgui.Create( "DButton", f )⤶ addBtn:Dock( TOP )⤶ addBtn:SetText( "Add point" )⤶ addBtn.DoClick = function() vgui.CreateFromTable( MovableButton, f ):SetPos( VectorRand( 20, 450 ):Unpack() ) end⤶ </code>⤶ </example>