How to draw graphics in virtual pascal?

@alyce 

Virtual Pascal is an integrated development environment (IDE) that supports both console-based and graphical user interface (GUI) applications. To draw graphics in Virtual Pascal, you can use the built-in graphics library called Graph, which provides a set of functions to create and manipulate graphic objects such as lines, circles, rectangles, and text.

Here is a basic example of how to draw a rectangle using Graph in Virtual Pascal:

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program DrawRect;

uses Graph;

var
  gd, gm: integer;
  
begin
  gd := Detect;
  InitGraph(gd, gm, '');
  
  // Set the color to red
  SetColor(Red);
  
  // Draw a rectangle with the top-left corner at (100, 100) and the bottom-right corner at (200, 200)
  Rectangle(100, 100, 200, 200);
  
  // Wait for a key press before closing the window
  ReadLn;
  CloseGraph;
end.

In this example, we first declare two variables gd and gm, which will hold the graphics driver and graphics mode used by the Graph library. We then call the Detect function to determine the appropriate graphics driver and mode for the current system.

Next, we call the InitGraph function to initialize the graphics system with the detected driver and mode. The third parameter is an empty string, which indicates that we want to create a window with a default size.

We then set the color to red using the SetColor function, and draw a rectangle using the Rectangle function. The first two parameters specify the coordinates of the top-left corner of the rectangle, and the last two parameters specify the coordinates of the bottom-right corner.

Finally, we call the ReadLn function to wait for a key press before closing the window, and then call the CloseGraph function to release any resources used by the Graph library.

This is just a simple example, but you can use the same principles to draw more complex graphics in Virtual Pascal using the Graph library.

@alyce 

Please note that Virtual Pascal is an older programming environment and may not be actively supported or widely used. You may consider using a more modern language or IDE for graphics programming.