/tools/jselect.lua

--
-- Selects joints
--
JSelectTool = {}
JSelectToolMT = { __index = JSelectTool }

setmetatable(JSelectTool, { __index = Tool })

function JSelectTool:Create(owner)
  local self = Tool:Create(owner, JSelectToolMT)

  return self
end

function JSelectTool:Destroy()
  Tool.Destroy(self)
end


function JSelectTool:MousePress(wx, wy, alt, shift, ctrl)
  local owner = self.owner
  local gstate = owner.gstate
  local scene = owner:get_scene()
  local selection = gstate.selection
  local selection2 = gstate.selection2
  local z = scene:GetZoom()
  local j, b = gstate:QueryAnchors(selection2, wx, wy, 5*z)
  if #j > 0 then
    owner:set_tool(AnchorTool, wx, wy, j[1], b[1])
    return
  end

  local q, j = gstate:QueryJoints(wx, wy, wx, wy, 5*z)
  if #q > 0 and alt == false and shift == false then
    local i = table.find(selection, q[1])
    if i then
      gstate:ShiftSelection(i, 1)
    else
      gstate:ClearSelection()
      gstate:AddToSelection({ q[1] }, { j[1] })
    end
    owner:set_tool(JTranslateTool, selection, selection2)
    owner.tool:MousePress(wx, wy, alt, shift)
  else
    self.alt, self.shift = alt, shift
    self.sx, self.sy = wx, wy
    if alt == true or shift == true then
      self.oldselect = { unpack(gstate.selection) }
      self.oldselect2 = { unpack(gstate.selection2) }
    else
      gstate:ClearSelection()
    end
  end
end

function JSelectTool:MouseMove(wx, wy, owx, owy)
  local sx, sy = self.sx, self.sy
  if sx == nil or sy == nil then
    return
  end 
  local scene = self.owner:get_scene()
  local gstate = self.owner.gstate
  self.ex, self.ey = wx, wy
  local z = scene:GetZoom()
  local q, s = gstate:QueryJoints(sx, sy, wx, wy, z*4)
  gstate:ClearSelection()
  if self.oldselect then
    gstate:AddToSelection(self.oldselect, self.oldselect2)
  end
  if self.alt == true then
    gstate:RemoveFromSelection(q, s)
  else
    gstate:AddToSelection(q, s)
  end
end

function JSelectTool:MouseRelease(wx, wy)
  self:MouseMove(wx, wy, wx, wy)
  self.alt, self.shift = nil, nil
  self.sx, self.sy = nil, nil
  self.ex, self.ey = nil, nil
  self.oldselect = nil
  self.oldselect2 = nil
end

function JSelectTool:Redraw(dt)
  local owner = self.owner
  local gstate = owner.gstate
  local scene = owner:get_scene()
  local camera = owner:get_camera()
  if self.ex and self.ey then
    local sx, sy = self.sx, self.sy
    local ex, ey = self.ex, self.ey
    scene:DrawLine(sx, sy, sx, ey, 1, WHITE, 1)
    scene:DrawLine(sx, ey, ex, ey, 1, WHITE, 1)
    scene:DrawLine(ex, ey, ex, sy, 1, WHITE, 1)
    scene:DrawLine(ex, sy, sx, sy, 1, WHITE, 1)
    scene:DrawStatus("Selecting joints (shift/alt to modify)")
    return
  end
  
  self:RedrawAnchors()
  
  local z = scene:GetZoom()
  local mx, my = mouse.xaxis, mouse.yaxis
  local wx, wy = camera:get_world_point(mx, my)
  if #gstate.selection > 0 then
    local f = "%d joint controls selected"
    local sz = string.format(f, #gstate.selection)
    scene:DrawStatus(sz)

    local j, b = gstate:QueryAnchors(gstate.selection2, wx, wy, 4*z)
    if #j > 0 then
      local f = "Anchor\n body:%d "
      local sz = string.format(f, b[1].id)
      scene:DrawTooltip(sz, wx, wy)
    end
  else
    scene:DrawStatus("Edit joints")
    
    local v, j = gstate:QueryJoints(wx, wy, wx, wy, 4*z)
    v = v[1]
    j = j[1]
    if v then
      local t = j:GetType()
      local sz
      if t == 'revolute' then
        if j:IsLimitEnabled() then
          local l = j:GetLowerLimit()
          local u = j:GetUpperLimit()
          sz = string.format("\n limits:%g, %g ", l, u)
        end
      elseif t == 'distance' then
        local len = j.def.length
        sz = string.format("\n length:%g ", len)
      elseif t == 'rope' then
        local len = j.def.maxLength
        sz = string.format("\n maxLength:%g ", len)
      elseif t == 'prismatic' then
        local ax, ay = j:GetWorldAxis()
        sz = string.format("\n axis:%g, %g", ax, ay)
        if j:IsLimitEnabled() then
          local l = j:GetLowerLimit()
          local u = j:GetUpperLimit()
          sz = sz .. string.format(" \n limits:%g, %g ", l, u)
        end
      elseif t == 'gear' then
        local j1 = j:GetJoint1().id
        local j2 = j:GetJoint2().id
        sz = string.format("\n joint1:%g \n joint2:%g", j1, j2)
      end
      sz = sz or ""
      local x, y = j.def.body1:GetWorldPoint(v.x, v.y)
      local cc = "false"
      if j.def.collideConnected == true then
        cc = "true"
      end
      local f = "Joint \n id:%d \n type:%s \n x:%g \n y:%g \n body1:%d \n body2:%d \n collideconnected: %s %s "
      local sz = string.format(f, j.id, t, x, y, j.def.body1.id, j.def.body2.id, cc, sz)
      scene:DrawTooltip(sz, wx, wy)
    end
  end
end

function JSelectTool:RedrawAnchors()
  local owner = self.owner
  local world = owner:get_world()
  local scene = owner:get_scene()
  local gstate = owner.gstate
  for i, anchor in ipairs(gstate.selection) do
    local joint = gstate.selection2[i]
    local b1, b2 = joint.def.body1, joint.def.body2
    if anchor == joint.def.localAnchor2 then
      b1, b2 = b2, b1
    end
    local wvx, wvy = anchor.x, anchor.y
    if anchor == joint.def.localAnchor1 or anchor == joint.def.localAnchor2 then
      wvx, wvy = b1:GetWorldPoint(anchor.x, anchor.y)
    end

    -- draw lines from the joint to the attached bodies
    local cm1x, cm1y = b1:GetWorldCenter()
    local z = scene:GetZoom()
    local dx, dy = (cm1x - wvx)/2, (cm1y - wvy)/2
    local cx, cy = wvx + dx, wvy + dy
    scene:DrawLine(wvx, wvy, cm1x, cm1y, 1, DARKORANGE, 1)
    --scene:DrawLine(cx, cy, cx + dy, cy - dx, 1, RED, 1)
    --scene:DrawCurve(wvx, wvy, cm1x, cm1y, cx + dy, cy - dx, 1, DARKORANGE, 1)
    scene:DrawImage("circle", cm1x, cm1y)
    local ox, oy = -9*z, -9*z
    local a, b = 1, 2
    if anchor == joint.def.localAnchor2 then
      ox = -ox
      a, b = b, a
    end
    scene:DrawImage("anchor" .. a, cm1x + ox, cm1y + oy)

    local type = joint:GetType()
    if type ~= 'distance' and type ~= 'prismatic' and type ~= 'rope' then
      local cm2x, cm2y = b2:GetWorldCenter()
      scene:DrawLine(wvx, wvy, cm2x, cm2y, 1, DARKORANGE, 1)
      scene:DrawImage("circle", cm2x, cm2y)
      scene:DrawImage("anchor" .. b, cm2x - ox, cm2y + oy)
    end
  end
end