modules/world: initial functions to compute camera size and positionning

gamecore/modules/world/camera.lua

@@ -48,6 +48,44 @@ function CameraSystem:initViews()
   self.views.list   = {}
   self.views.basewidth, self.views.baseheight   = core.screen:getDimensions()
   self.views.width,     self.views.height       = self:getViewsDimensions()
+
+  self.views.posList = {}
+  self.views.posList.dual   = {}
+  self.views.posList.multi  = {}
+
+  if (self.verticalSplit) then
+    self.views.posList.dual[1] = {}
+    self.views.posList.dual[1].x = 0
+    self.views.posList.dual[1].y = -(self.views.baseheight/4)
+
+    self.views.posList.dual[2] = {}
+    self.views.posList.dual[2].x = 0
+    self.views.posList.dual[2].y = (self.views.baseheight/4)
+  else
+    self.views.posList.dual[1] = {}
+    self.views.posList.dual[1].x = (self.views.basewidth/4)
+    self.views.posList.dual[1].y = 0
+
+    self.views.posList.dual[2] = {}
+    self.views.posList.dual[2].x = -(self.views.basewidth/4)
+    self.views.posList.dual[2].y = 0
+  end
+
+  self.views.posList.multi[1] = {}
+  self.views.posList.multi[1].x = -(self.views.basewidth /4)
+  self.views.posList.multi[1].y = -(self.views.baseheight/4)
+
+  self.views.posList.multi[2] = {}
+  self.views.posList.multi[2].x =  (self.views.basewidth /4)
+  self.views.posList.multi[2].y = -(self.views.baseheight/4)
+
+  self.views.posList.multi[3] = {}
+  self.views.posList.multi[3].x = -(self.views.basewidth /4)
+  self.views.posList.multi[3].y =  (self.views.baseheight/4)
+
+  self.views.posList.multi[4] = {}
+  self.views.posList.multi[4].x = (self.views.basewidth /4)
+  self.views.posList.multi[4].y = (self.views.baseheight/4)
 end
 
 -- INFO FUNCTIONS
@@ -61,36 +99,67 @@ function CameraSystem:haveView()
   return (self:getViewNumber() == 0)
 end
 
-function CameraSystem:getViewsDimensions()
+function CameraSystem:getViewsDimensions(viewNumber)
   local basewidth, baseheight = self.views.basewidth, self.views.baseheight
-  local viewnumber = self:getViewNumber()
+  local viewnumber = viewNumber or self:getViewNumber()
 
   if (viewnumber <= 1) then
     return basewidth,       baseheight
   elseif (viewnumber == 2) then
     if (self.verticalSplit) then
-      return (basewidth/2), (baseheight)
+      return (basewidth),     (baseheight/2)
     else
-      return (basewidth),   (baseheight/2)
+      return (basewidth/2),   (baseheight)
     end
   else
     return (basewidth/2),   (baseheight/2)
   end
 end
 
+function CameraSystem:recalculateViewsPositions()
+  if #self.views.list == 1 then
+    self.views.list[1].pos.onScreen.x = 0
+    self.views.list[1].pos.onScreen.y = 0
+  else
+    for i,v in ipairs(self.views.list) do
+      local x, y = self:getViewPositions(i)
+      self.views.list[i].pos.onScreen.x = x
+      self.views.list[i].pos.onScreen.y = y
+    end
+  end
+end
+
+function CameraSystem:getViewPositions(id)
+  local viewNumber = #self.views.list
+
+  if (viewNumber == 2) and (id == 1) or (id == 2) then
+    return self.views.posList.dual[id].x,   self.views.posList.dual[id].y
+  elseif (viewNumber > 2) and ((id >= 1) or (id <= 4)) then
+    return self.views.posList.multi[id].x,  self.views.posList.multi[id].y
+  end
+
+end
+
 -- WRAPPER and UTILS
 -- Access data from the views
 
 function CameraSystem:addView(x, y)
   if (#self.views.list < SCREEN_LIMIT) then
+    local id = #self.views.list + 1
     local view = {}
 
-    view.cam    = View(x, y, 1, 0, true)
+    view.pos = {}
+    view.pos.x = x or 0
+    view.pos.y = y or 0
+    view.pos.onScreen = {}
+
+    view.cam    = View(view.pos.x, view.pos.y, 1, 0, true)
     -- TODO: add a target system in order to make a camera able
     -- to target a specific object
 
     table.insert(self.views.list, view)
     self.views.width, self.views.height = self:getViewsDimensions()
+    self:recalculateViewsPositions()
   end
 end
 
@@ -132,10 +201,47 @@ function CameraSystem:getViewCoordinate(id)
   return camx, camy, camh, camw
 end
 
+function CameraSystem:getOnScreenViewCoordinate(id)
+  local view = self:getView(id)
+
+  local viewx, viewy, vieww, viewh
+  local basex, basey = (self.views.basewidth  / 2), (self.views.baseheight / 2)
+  viewx   = (basex) + view.pos.onScreen.x - (self.views.width   / 2)
+  viewy   = (basey) + view.pos.onScreen.y - (self.views.height  / 2)
+
+  vieww   = self.views.width
+  viewh   = self.views.height
+  return viewx, viewy, vieww, viewh
+end
+
+function CameraSystem:getOnScreenViewCenter(id)
+  local view = self:getView(id)
+
+  local viewx, viewy
+  local basex, basey = (self.views.basewidth  / 2), (self.views.baseheight / 2)
+  viewx   = (basex) + view.pos.onScreen.x
+  viewy   = (basey) + view.pos.onScreen.y
+
+  return viewx, viewy
+end
+
 function CameraSystem:getViewScale(id)
   local cam = self:getViewCam(id)
 
   return cam.scale
 end
 
+function CameraSystem:drawDebugViewBox()
+  for i=1, #self.views.list do
+    local viewx, viewy, vieww, viewh = self:getOnScreenViewCoordinate(i)
+    utils.graphics.box(viewx, viewy, vieww, viewh)
+
+
+    local xx, yy = self:getOnScreenViewCenter(i)
+    love.graphics.line(xx-3, yy, xx+3, yy)
+    love.graphics.line(xx, yy-3, xx, yy+3)
+    print(viewx, viewy, vieww, viewh)
+  end
+end
+
 return CameraSystem