_PRINTSTRING - QB64 Wiki

_PRINTSTRING

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The _PRINTSTRING statement prints text strings using graphic column and row coordinate positions.


Contents

Syntax

_PRINTSTRING(column, row), textExpression$[, imageHandle&]


Parameters

  • column and row are INTEGER or LONG starting PIXEL (graphic) column and row coordinates to set text or custom fonts.
  • textExpression$ is any literal or variable string value of text to be displayed.
  • imageHandle& is the optional image or destination to use. Zero designates current SCREEN page.


Description

  • The starting coordinate sets the top left corner of the text to be printed. Use _FONTHEIGHT to calculate that text or font position
  • The _FONT size can affect the screen and row heights.
    • Custom fonts are not required. _PRINTSTRING can print all ASCII characters.
  • _PRINTWIDTH can be used to determine how wide a text print will be so that the screen width is not exceeded.
  • If the imageHandle& is omitted, the current image, page or screen destination is used.
  • Can use the current font alpha blending with a designated image background. See the _RGBA function example.
  • Use the _PRINTMODE statement before printing to set how the background is rendered.
  • In SCREEN 0 (text only), _PRINTSTRING works as one-line replacement for LOCATE x, y: PRINT text$, without changing the current cursor position.


Availability

  • In versions of QB64 prior to 1.000 _PRINTSTRING can only be used in graphic, 256 color or 32 bit screen modes, not SCREEN 0.


Examples

Example 1: Printing those unprintable ASCII control characters is no longer a problem!

SCREEN _NEWIMAGE(800, 600, 256) FOR code = 0 TO 31 chrstr$ = chrstr$ + CHR$(code) + SPACE$(1) NEXT _FONT _LOADFONT("C:\Windows\Fonts\Cour.ttf", 20, "MONOSPACE") 'select monospace font _PRINTSTRING (0, 16), chrstr$ END

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Example 2: Making any QB64 program window larger using a SUB that easily converts PRINT to _PRINTSTRING.

Scr13& = _NEWIMAGE(320, 200, 13) 'this is the old SCREEN 13 image page to set the image Big13& = _NEWIMAGE(640, 480, 256) 'use 4 X 3 aspect ratio that Qbasic used when full screen SCREEN Big13& _DEST Scr13& image1& = _LOADIMAGE("Howie.BMP", 256) image2& = _LOADIMAGE("Howie2.BMP", 256) _PUTIMAGE (10, 20), image1&, Scr13& _PUTIMAGE (160, 20), image2&, Scr13& _COPYPALETTE image1&, Scr13& COLOR 151: LOCATE 2, 4: PRINTS "Screen 13 Height Reduction to 83%" LOCATE 22, 22: PRINTS CHR$(24) + " 4 X 3 Proportion" 'use concatenation LOCATE 24, 21: PRINTS CHR$(27) + " Stretched at 100%" 'instead of a semicolon! _COPYPALETTE Scr13&, Big13& 'required when imported image colors are used _PUTIMAGE , Scr13&, Big13& 'stretches the screen to double the size K$ = INPUT$(1) END SUB PRINTS (Text$) row% = (CSRLIN - 1) * _FONTHEIGHT 'finds current screen page text or font row height col% = (POS(0) - 1) * _PRINTWIDTH("W") 'finds current page text or font column width _PRINTSTRING (col%, row%), Text$ END SUB

Code by Ted Weissgerber
Explanation: The procedure above creates a larger version of a SCREEN 13 window by stretching it with _PUTIMAGE. It cannot stretch PRINTed text so _PRINTSTRING must be used instead. LOCATE sets the PRINT cursor position for CSRLIN and POS(0) to read. The SUB then converts the coordinates to graphical ones. Then change PRINT to PRINTS using the IDE Search Menu.
Download of Example 2 Bitmap images


Example 3: Rotating a text string around a graphic object.

SCREEN 12 DIM row AS INTEGER, cnt AS INTEGER, cstart AS SINGLE, cend AS SINGLE DIM xrot AS INTEGER, yrot AS INTEGER, scale AS INTEGER ' _FULLSCREEN 'full screen optional cstart = 0: cend = 8 * ATN(1) xrot = 6: yrot = 60: scale = 4 row = 1 CIRCLE (320, 240), 15, 9: PAINT STEP(0, 0), 9 DO FOR i = cstart TO cend STEP .04 x = 300 + (scale * 40 - (row * xrot)) * COS(i) y = 200 + (scale * 40 - (row * yrot)) * SIN(i) cnt = cnt + 1 COLOR 7: _PRINTSTRING (x, y), "HELLO WORLD!", 0 'display IF cnt = LEN(text$) * 8 THEN cnt = 0: EXIT DO _DISPLAY COLOR 0: _PRINTSTRING (x, y), "HELLO WORLD!", 0 'erase _DELAY 0.02 NEXT LOOP UNTIL INKEY$ = CHR$(27) 'escape key exit COLOR 15 END

Adapted from code by Unseen Machine


See also



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