ManualVertices = class("ManualVertices")

function ManualVertices:ctor(vertexFormat)
	-- 自动计算的包围盒
	self._boundingBox = nil;
	-- 顶点缓冲区
	self._vertices = {};
	-- 顶点格式
	self._vertexFormat = vertexFormat;

	self._vertexElementOffset = {};
	self._vertexElementSize = {};

	-- 顶点的float元素个数
	self._vertexSize = 0;
	for i , v in ipairs(self._vertexFormat) do
		self._vertexElementOffset[v.usage] = self._vertexSize + 1;
		self._vertexElementSize[v.usage] = self._vertexSize;
		self._vertexSize = self._vertexSize + v.size
	end

	-- 当前颜色
	self._color = cc.c4f(1,1,1,1);
end

local function createVertex(num)
	local vertex = {};
	for i = 1 , num do
		table.insert(vertex , 0);
	end
	return vertex
end

function ManualVertices:setVertexPos(vertex , pos)
	local offset = self._vertexElementOffset[cc.VertexFormatUsage.POSITION];
	vertex[offset] = pos.x or 0;
	vertex[offset + 1] = pos.y or 0;
	vertex[offset + 2] = pos.z or 0;
end

function ManualVertices:setVertexColor(vertex , color)
	local offset = self._vertexElementOffset[cc.VertexFormatUsage.COLOR];
	vertex[offset] = color.r or 0;
	vertex[offset + 1] = color.g or 0;
	vertex[offset + 2] = color.b or 0;
	vertex[offset + 3] = color.a or 0;
end

function ManualVertices:insertVertex(vertex)
	local offset = self._vertexElementOffset[cc.VertexFormatUsage.POSITION];
	local pos = cc.vec3(vertex[offset] , vertex[offset + 1] , vertex[offset + 2]);
	if self._boundingBox == nil then
		self._boundingBox = cc.BoundingBox:new(pos , pos);
	end
	self._boundingBox:merge(pos);

	for i , v in ipairs(vertex) do
		table.insert(self._vertices , v);
	end
end

function ManualVertices:createVertex()
	local vertex = createVertex(self._vertexSize);
	self:setVertexColor(vertex , self._color);
	return vertex;
end

-- 获取顶点数据
function ManualVertices:getVertices()
	return self._vertices;
end

-- 获得顶点个数
function ManualVertices:getVertexCount()
	return #self._vertices / self._vertexSize;
end


-- 获取包围盒
function ManualVertices:getBoundingBox()
	return self._boundingBox;
end

-- 设置当前颜色
function ManualVertices:setColor(color)
	self._color = color;
end

-- 画一根线
function ManualVertices:drawLine(startPos , endPos)
	local vertex;
	
	vertex = self:createVertex();
	self:setVertexPos(vertex , startPos);
	self:insertVertex(vertex);

	vertex = self:createVertex();
	self:setVertexPos(vertex , endPos);
	self:insertVertex(vertex);
end

-- 画一个矩形
function ManualVertices:drawRect(leftTop , rightTop , leftBottom , rightBottom)
	local vertex;
	
	vertex = self:createVertex();
	self:setVertexPos(vertex , leftTop);
	self:insertVertex(vertex);
	
	vertex = self:createVertex();
	self:setVertexPos(vertex , rightTop);
	self:insertVertex(vertex);
	
	vertex = self:createVertex();
	self:setVertexPos(vertex , leftBottom);
	self:insertVertex(vertex);

	
	vertex = self:createVertex();
	self:setVertexPos(vertex , leftBottom);
	self:insertVertex(vertex);
	
	vertex = self:createVertex();
	self:setVertexPos(vertex , rightTop);
	self:insertVertex(vertex);
	
	vertex = self:createVertex();
	self:setVertexPos(vertex , rightBottom);
	self:insertVertex(vertex);
end