Getting Started with QBASIC Graphics
QBASIC’s graphics commands were straightforward yet powerful, allowing users to create impressive visuals. To begin, users needed to enable graphics mode using the SCREEN command and pick a resolution. The popular choice was SCREEN 13, offering 320×200 pixel resolution and 256 colors.
SCREEN 13 ' Enable graphics mode with resolution 320x200 and 256 colors
Drawing Basic Shapes
Once you enter graphics mode in QBASIC, you can draw different shapes and patterns on the screen. QBASIC provides simple commands like LINE (for drawing lines), CIRCLE (for circles), RECT (for rectangles), and PAINT (for filling enclosed areas with color) to help you create your designs.
' Draw a line LINE (50, 50)-(200, 100), 15 ' Draws a line from (50, 50) to (200, 100) with color 15 (white) ' Draw a circle CIRCLE (160, 100), 50, 14 ' Draws a circle with center (160, 100), radius 50, and color 14 (yellow) ' Draw a rectangle RECT (100, 150)-(220, 180), 6, , 1 ' Draws a rectangle from (100, 150) to (220, 180) with color 6 (cyan) and border color 1 (black) ' Fill an enclosed area with color PAINT (250, 50), 9, 4 ' Fills the enclosed area at (250, 50) with color 9 (blue) and boundary color 4 (red)
With QBASIC’s graphics capabilities, you can create fascinating animations. By regularly updating the screen and moving objects around, you can achieve captivating and dynamic visual effects.
Here’s an example of a simple animation that moves a circle across the screen:
SCREEN 13 ' Enable graphics mode ' Set initial coordinates DIM x, y x = 160 y = 100 DO CLS ' Clear the screen CIRCLE (x, y), 50, 14 ' Draw the circle at the new coordinates x = x + 2 ' Increment x coordinate to move the circle horizontally IF x > 320 THEN x = 0 ' Reset x coordinate when the circle moves off the screen SLEEP 15 ' Introduce a delay to control animation speed LOOP UNTIL INKEY$ <> "" ' Exit animation loop when a key is pressed
Implementing Interactive Graphics
Graphics programming in QBASIC offers more than just basic animations; it can involve user interaction as well. You can make graphics applications that respond to user input, like mouse clicks or keyboard presses, to create interactive and engaging experiences.
SCREEN 13 ' Enable graphics mode DO ' Check for mouse input IF LEN(INKEY$) = 0 THEN LOCATE 1, 1: PRINT "Move the mouse to draw!" DO WHILE LEN(INKEY$) = 0 mx = MOUSEX ' Get mouse X coordinate my = MOUSEY ' Get mouse Y coordinate ' Draw a point at the current mouse position PSET (mx, my), 15 LOOP END IF ' Check for keyboard input IF INKEY$ <> "" THEN LOCATE 1, 1: PRINT "Press any key to clear the screen!" CLS ' Clear the screen when a key is pressed END IF LOOP UNTIL INKEY$ = CHR$(27) ' Exit loop when Esc key is pressed
Creating Your Artistic Masterpieces
QBASIC graphics programming provides a creative canvas to express yourself. You can combine shapes, colors, animations, and interactivity to create mesmerizing visuals through code. Whether you’re a beginner or an experienced developer, QBASIC graphics is a fun and unique way to explore your creativity. As you delve deeper into QBASIC graphics, you’ll find more exciting techniques like pixel manipulation, sprite animations, and fractal art generation. The possibilities are endless!