從表單中獲取特定大小的矩形

Question

我可以從我的表單（backbufferdata）中獲取「屏幕截圖」，但是是否可以只取其一部分？可以說，如果我的表單是1600x800像素，是否有可能只獲得100x100像素？

int w = GraphicsDevice.PresentationParameters.BackBufferWidth; 
int h = GraphicsDevice.PresentationParameters.BackBufferHeight; 

//pull the picture from the buffer 
int[] backBuffer = new int[w * h]; 
GraphicsDevice.GetBackBufferData(backBuffer); 

//copy into a texture 
Texture2D texture = new Texture2D(GraphicsDevice, w, h, true, GraphicsDevice.PresentationParameters.BackBufferFormat); 
texture.SetData(backBuffer); 

如果我改變寬度和高度，它會給出一個錯誤「它太小或太大」。

Answer 1

嘗試使用GraphicsDevice.GetBackBufferData通用方法（可爲空的，T []，的Int32，Int32）將

作爲例子：

int posX = 0; // area position 
int posY = 0; 
int w = 200; // area size 
int h = 100; 

//pull the picture from the buffer 
int[] backBuffer = new int[w * h]; 
GraphicsDevice.GetBackBufferData(new Rectangle(posX, posY, w, h), backBuffer, 0, w*h); 

//copy into a texture 
Texture2D texture = new Texture2D(GraphicsDevice, w, h, true, GraphicsDevice.PresentationParameters.BackBufferFormat); 
texture.SetData(backBuffer);