PRINTSTRING: Difference between revisions

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




{{PageDescription}}
{{PageDescription}}
* The starting coordinate sets the top left corner of the text to be printed. Use [[_FONTHEIGHT]] to calculate that text or [[_FONT|font]] position
* The starting coordinate sets the top left corner of the text to be printed. Use [[_FONTHEIGHT]] to calculate that text or [[_FONT|font]] position
* The [[_FONT]] size can affect the [[SCREEN (statement)|screen]] and row heights.
* The [[_FONT]] size can affect the [[screen]] and row heights.
** Custom fonts are not required. [[_PRINTSTRING]] can print all [[ASCII]] characters.
** 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.
* [[_PRINTWIDTH]] can be used to determine how wide a text print will be so that the screen width is not exceeded.
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Big13& = {{Cl|_NEWIMAGE}}(640, 480, 256) 'use 4 X 3 aspect ratio that QBasic used when full screen
Big13& = {{Cl|_NEWIMAGE}}(640, 480, 256) 'use 4 X 3 aspect ratio that QBasic used when full screen


{{Cl|SCREEN (statement)|SCREEN}} Big13&
{{Cl|SCREEN}} Big13&
{{Cl|_DEST}} Scr13&
{{Cl|_DEST}} Scr13&
image1& = {{Cl|_LOADIMAGE}}("Howie.BMP", 256)
image1& = {{Cl|_LOADIMAGE}}("Howie.BMP", 256)
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''Example 3:'' Rotating a text string around a graphic object.
''Example 3:'' Rotating a text string around a graphic object.
{{CodeStart}}
{{CodeStart}}
{{Cl|SCREEN (statement)|SCREEN}} 12
{{Cl|SCREEN}} 12
{{Cl|DIM}} row {{Cl|AS}} {{Cl|INTEGER}}, cnt {{Cl|AS}} {{Cl|INTEGER}}, cstart {{Cl|AS}} {{Cl|SINGLE}}, cend {{Cl|AS}} {{Cl|SINGLE}}
{{Cl|DIM}} row {{Cl|AS}} {{Cl|INTEGER}}, cnt {{Cl|AS}} {{Cl|INTEGER}}, cstart {{Cl|AS}} {{Cl|SINGLE}}, cend {{Cl|AS}} {{Cl|SINGLE}}
{{Cl|DIM}} xrot {{Cl|AS}} {{Cl|INTEGER}}, yrot {{Cl|AS}} {{Cl|INTEGER}}, scale {{Cl|AS}} {{Cl|INTEGER}}
{{Cl|DIM}} xrot {{Cl|AS}} {{Cl|INTEGER}}, yrot {{Cl|AS}} {{Cl|INTEGER}}, scale {{Cl|AS}} {{Cl|INTEGER}}

Revision as of 10:53, 26 January 2023

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


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.
  • _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
  ☺ ☻ ♥ ♦ ♣ ♠ • ◘ ○ ◙ ♂ ♀ ♪ ♫ ☼ ► ◄ ↕ ‼ ¶ § ▬ ↨ ↑ ↓ → ← ∟ ↔ ▲ ▼


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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