BLOAD - QB64Official/qb64 GitHub Wiki

BLOAD loads a binary graphics file created by BSAVE to an array.

Legacy Support

  • QB64 can load larger arrays directly from binary files using PUT # and GET # without BLOAD. For that reason, BLOAD isn't recommended practice anymore and is supported to maintain compatibility with legacy code.

Syntax

BLOAD fileName$, VARPTR(imageArray%(Parameter))

Parameter(s)

  • fileName$ is the name of the file that the image should be BSAVEd to.
  • imageArray%(index) is the INTEGER arrays start index to store the image loaded.

Description

  • There must be an INTEGER array of adequate size (up to 26K) to hold the graphic data.
  • A DEF SEG pointing to the array is required. DEF SEG = VARSEG(imageArray%(index))
  • index is the starting image element of the Array. Can also include RGB color settings at the start index.
  • Fullscreen images in SCREEN 12 require 3 file BLOADs. A 26K array can hold 1/3 of screen.
  • Custom RGB color settings can be embedded(indexed) at the start of the image array.
  • BLOAD can be used to load any array that was saved with BSAVE, not just graphics.
  • Array sizes are limited to 32767 Integer elements due to use of VARPTR in QBasic and QB64's emulated conventional memory.

Example(s)

Loading data to an array from a BSAVED file.


DEF SEG = VARSEG(Array(0))
  BLOAD filename$, VARPTR(Array(LBOUND(Array))) ' changeable index
DEF SEG

Explanation: Referance any type of array that matches the data saved. Can work with Integer, Single, Double, Long, fixed length Strings or TYPE arrays. LBOUND determines the starting offset of the array or another index could be used.

Using a QB default colored image.


DEF SEG = VARSEG(Image%(0)) ' pointer to first image element of an array
  BLOAD FileName$, VARPTR(Image%(0)) ' place data into array at index position 0
  PUT(Col, Row), Image%(0), PSET ' Put the image on the screen from index 0
DEF SEG

Note: PSET is used as a PUT (graphics statement) action that places the image over any background objects.

See Also