10-Marble

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How to create a numeric value as a bitmap?

Forum|Forum|8 months ago
July 29, 2025
3 replies
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I create parametric bitmaps that depend on the values of the calculated variables ~~using the READ_BLUE function~~.
How to insert a numeric value into such a picture as a bitmap that changes depending on the calculated variables?

2_01.zip

Mathcad Usage

Best answer by Werner_E

@DD_13910355 wrote:

I create parametric bitmaps that depend on the values of the calculated variables using the READ_BLUE function.
How to insert a numeric value into such a picture as a bitmap that changes depending on the calculated variables?

READ_BLUE?

You created a grayscale picture right from scratch.

Is your intention to actually see for instance the x-coordinate "a=30" of the circle center written pixelwise in the picture matrix?

There is no method Mathcad would offer right out of the box, but you sure could write your own.

You would have to create a vector of bitmaps matrices for all letters and numbers first, and then split the number into its individual digits (either by continuously using mod 10 or by turning the number into a string via "num2str" and access the individual characters), select the appropriate bitmap from your vector of bitmaps, scale it as desired and combine it with the picture bitmap.

Quite some work but sure possible to do. Only worth the effort if your really need it quite often.

How about saving the bitmap to a file with the changing values being part of the file name? Would this help? Or is it mandatory that you actually SEE the numbers (which ones) in the picture?

T

terryhendicott

21-Topaz II

Hi,

Add some colour:-

Cheers

Terry

1_250729-01.zip

W

Werner_E

Answer

25-Diamond I

@DD_13910355 wrote:

I create parametric bitmaps that depend on the values of the calculated variables using the READ_BLUE function.
How to insert a numeric value into such a picture as a bitmap that changes depending on the calculated variables?

READ_BLUE?

You created a grayscale picture right from scratch.

Is your intention to actually see for instance the x-coordinate "a=30" of the circle center written pixelwise in the picture matrix?

There is no method Mathcad would offer right out of the box, but you sure could write your own.

You would have to create a vector of bitmaps matrices for all letters and numbers first, and then split the number into its individual digits (either by continuously using mod 10 or by turning the number into a string via "num2str" and access the individual characters), select the appropriate bitmap from your vector of bitmaps, scale it as desired and combine it with the picture bitmap.

Quite some work but sure possible to do. Only worth the effort if your really need it quite often.

How about saving the bitmap to a file with the changing values being part of the file name? Would this help? Or is it mandatory that you actually SEE the numbers (which ones) in the picture?

D

DD_13910355

Author

10-Marble

"READ_BLUE?"

I was wrong.

W

Werner_E

25-Diamond I

I could not be bother to create functions for adding letters and numbers in pixel graphics, but here are some functions which may make it easier to add lines, circles and rectangles (either outlines or filled) in a pixel matrix. The functions were written for grayscale imaged as the one used by you, but could easily be adopted for color images as well. Actually a color image is just a vector consisting of three grayscale images, one for each primary color.

Other geometric primitives could be added and adding texts may use a similar approach.

MC15 sheet attached

1_WE_20250729_Pixelgraphics.zip

W

Werner_E

25-Diamond I

@terryhendicott wrote:

Hi,

A great Mathcad handbook was released on image creation that has three fonts that can be put into 2D images.

It does exactly as Werner proposed.

Careful! It is, of course, always worthwhile to take a look at the excellent work of Prof. Byrkeland, but his work deals ‘only’ with classic xy plots,. The fonts he privides in the three "Font0x.xmcd" sheets actually are vector graphics, not pixel graphics as would be needed in the picture of the questioner.

W

Werner_E

25-Diamond I

I could not resist 😉

Here is a basic function to add text to a bitmap graphic.

Feel free to add bold, italic or rotation.

Because of the 'reversed' x-axis, xpos/ypos denote the position of upper left corner of the text bitmap.

The characters were created by using the screenshot of a text page written in a monospace font.

Word file and screenshot image are attached but not needed for the Mathcad sheet to run. The data is already embedded in the Mathcad sheet.

Initially I used the higher resolution file characters.bmp but autosave (which I have set to activate every few minutes) took quite long and this was annoying. So I used the scaled down characters3.bmp.

1_characters.docx

2_WE_20250730_Pixelgraphics.zip

T

terryhendicott

21-Topaz II

Hi

It seems the gaming industry uses bitmap fonts for high speed text to monitor pixels so the solutions are available for professional results. One solution that gives any choice of font (TTF etc) and any reasonable size of bitmap font is the online site:

https://snowb.org/

The product of using the site is twofold. A packed nested image in *.PNG format of the individual charecters, and a text file *.fnt extension giving enough information to unpack individual character bitmaps. The information in a text file is the position in the packed matrix, the size of the character bitmap, and offsets to place the character image into a line of text.

To work in Mathcad 15 the PNG file needs to be changed to a BMP file and this is achievable in most graphics programs. I used photoshop saving as a 24 bit BMP.

To also work in Mathcad 15 the text file needs to be edited to turn the fnt file into a prn file. First delete the first four lines of headers. Remainder of lines in the fnt file are like this:

char id=36 x=60 y=68 width=10 height=15 xoffset=-1 yoffset=-1 xadvance=9 page=0 chnl=15

Simply edit/replace "char id=" etc with nothing over the whole file to get:

36 60 68 10 15 -1 -1 9 0 15

Mathcad 15 can read this file into data By default there are five missing characters when you open the online bitmap font generator. They are "<>\`~" and should be added for Mathcad matrix to be complete. The results are excellent and very professional.