RAPTOR Syntax and Semantics
Graphic window opening and closing procedures Open_Graph_Window( X_Size, Y_Size ) Close_Graph_Window Graphic window “size” functions Get_Max_Width -> returns available screen pixel width Get_Max_Height -> returns available screen pixel height Get_Window_Width -> returns current window pixel width Get_Window_Height -> returns current window pixel height Keyboard input procedure Wait_For_Key Keyboard input functions Key_Hit -> returns True / False (whether a key was pressed) Get_Key -> returns the numeric ASCII value of the pressed key Get_Key_String -> returns a string value of the pressed key Drawing procedures Put_Pixel( X, Y, Color ) Draw_Line( X1, Y1, X2, Y2, Color ) Draw_Box( X1, Y1, X2, Y2, Color, Filled/Unfilled ) Draw_Circle( X, Y, Radius, Color, Filled/Unfilled ) Draw_Ellipse( X1, Y1, X2, Y2, Color, Filled/Unfilled ) Draw_Arc( X1, Y1, X2, Y2, StartX, StartY, EndX, EndY, Color ) Clear_Window( Color ) Flood_Fill( X, Y, Color ) Display_Text( X, Y, String Expression, Color ) Display_Number( X, Y, Number Expression, Color ) Mouse input procedures Wait_for_Mouse_Button( Which_Button ) Get_Mouse_Button( Which_Button, X, Y ) Mouse input functions Mouse_Button_Pressed( Which_Button ) –> returns True / False Mouse_Button_Released( Which_Button ) –> returns True / False Get_Mouse_X –> returns X coordinate of mouse location Get_Mouse_Y –> returns Y coordinate of mouse location RAPTORGraph Syntax and Semantics How to animate an object in RAPTORGraph Place the following inside of a loop Draw some an object relative to an X,Y point with the drawing procedures Delay_For some small time period Draw the object again in white (i.e. erase it) Update the X,Y point where you are drawing by some small offset RAPTORGraph Colors Black, Blue, Green, Cyan, Red, Magenta, Brown, Light_Gray, Dark_Gray, Light_Blue, Light_Green, Light_Cyan, Light_Red, Light_Magenta, Yellow, White (Get_Pixel returns 0 for Black, 1 for Blue, …,16 for White) Graphics window query function Get_Pixel( X, Y ) -> returns the number code for the color of the pixel at (X, Y) Iteration Statement (loop statement) –
An Iteration statement enables a group of statements to be executed more than once. Use I.T.E.M (Initialize, Test, Execute, and Modify) to ensure your loop (and loop control variable) are correct. A Condition Controlled Loop (basic loop) repeats its statements until a condition (the decision statement) becomes true. The validation loop above will continue to execute until the user enters a number between 1 and 10. Number is the loop control variable. A Count Controlled Loop repeats its statements a fixed number of times. (This executes the loop 100 times because of the decision: Count >= 100). The count controlled loop above executes exactly 10 times
(it displays the numbers 1 through 10 and the squares of those numbers). Count is the loop control variable. Initialize (and modify)
the loop control variable Test the loop
control variable Initialize the loop control variable (above the loop) Modify the loop control variable Test the loop
control variable Execution step Execution step Selection Statement - A selection statement is used to decide whether or not to do something, or to decide which of several things (if any) to do. If the Boolean Expression is TRUE, execute the left hand path
otherwise execute the right hand path If the value of the variable GPA is greater than 3.0 then execute the statement
Put("Dean’s List") otherwise do nothing If a student’s GPA is less than 2.0 then execute the statement
Put("Academic probabtion") otherwise execute the statement Put("Cadet in good standing") This last example requires several decision statements as there are several decisions (more than two possible paths). The code assigns a nominal “grade” based on a student’s GPA. The “pattern” of these selection statements is called cascading selections. RAPTOR Syntax and Semantics – Selection and Iteration Control Structures