FSX How to create BMP files for masking purposes ?


I have some Saitek's Flight Instrument Panels (FIPs) and I am trying to modify some of the default gauges and create my own.

However, I found the bmp files created for masking purposes by PhotoShop are not recognized by the gauges.

For example, I have created one named AirSpeed_mask.bmp with PS

<MaskImage Name="AirSpeed_mask.bmp" ImageSizes="64,20,64,20">

It just blocks the space I want them to work as masks.

I've tried resizing mask images from other existed gauges with PS or Paint. These mask images work originally. When they are modified, they sometimes work, and sometimes don't.

I am quite frustrating.

Wonder if anyone could tell me how to create this type of bmp files for masking purposes for Saitek's FIP properly in the first place? I'd appreciate it very much.
Thanks for the note, Bill.

I have saved different bit versions (1, 8, 24 etc) and none of them successful. I know the color of the file cannot be 000000. So I am using 010101. But still, not successful. Don't know if I have missed something.

Have asked Saitek for help. Their answer is:

We are unable to offer this information as it is privileged and confidential. We are unable to provide instruction on creating gauges to customers.
Really can't understand the point of confidentiality for the format of these masking files !

Are they afraid that we are making gauges to compete with them? :mad::mad:


Resource contributor
As I remember, the part of the image that should be the "window" should be 1,1,1 (RGB). The rest of the image (if any) should be 0,0,0.

Hope this helps,
Thanks Tom. RGB 1,1,1 equals to 010101.
Do you mean the margin (or part) of the image should be in 1,1,1 and the remaining part in 0,0,0 ?
I'll give a try and it's not successful.
Did I miss your point?
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Resource contributor
Only the area of the displayed bitmap you want to be seen should be 1,1,1. The rest of the area must be 0,0,0.

The simple way of picturing this is this: you have a "wall" to paint transparent. Only the "window" in that wall should be painted 1,1,1. :D


Resource contributor

In my gauges I have an Axis statement as well, but I don't know if that is required or not.

   <MaskImage Name="elev_trim_mask.bmp" ImageSizes="24,25">
         <Axis X="0" Y="0"/>
I have a Spill Gauge with four elements.
A background
A Semi circular disk
A mask with a quadrant cutout
An overlay with a white bar also with a quadrant cutout.

The semi circular disk indicates by how much the valve is open and is controlled by a joystick switch function.
The overlay with the white bar indicates whether the valve is crosslined ie. closed or open.
Both have axes.
<Gauge Name="Left Spill Indicator" Version="1.0">
   <Image Name="spillmask.bmp" Luminous="1"/>

      <Position X="200" Y="206"/>
      <Image Name="L_SPILL_IND.bmp" PointsTo="North" Luminous="1">
         <Axis X="146" Y="146"/>
          <Value Minimum="0" Maximum="100">(L:spill_segment,enum)</Value>
            <Item Value="0" X="200" Y="344"/>
            <Item Value="25" X="146" Y="339"/>
            <Item Value="100" X="60" Y="240"/>
         <Delay DegreesPerSecond="30"/>

      <Position X="0" Y="0"/>
      <Image Name="L_Spill Indicator.bmp"/>

      <Position X="188" Y="188"/>
      <Image Name="bar_1.bmp" PointsTo="North" Luminous="1">
         <Axis X="188" Y="188"/>
         <Value>(L:spill_segment,enum) 0 &gt;
if{ 1 } els{ 0 }</Value> 
            <Item Value="0" X="17" Y="188"/>
            <Item Value="1" X="171" Y="33"/>           
         <Delay DegreesPerSecond="160"/>

      <Tooltip>Left Spill Indicator-%( (L:spill_segment,enum) )%{if}In-Line%{else}Cross_Lined%{end}</Tooltip>


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Thank you Bill, Tom and Vololiberista. :)

I have figured out how to create such *.bmp files for masking purpose with the help from you all. It's simple and I just need to:

1) Fill an image file (to be used as mask) with RGB color=1,1,1 or web color=010101; then

2) Save the file in 1, 24, or 32-bit mode.

That's it!

It's so disgusting that the Saitek EU technical guy, Gabriel Constantinescu, replied and claimed such information as "privileged and confidential to the company" and cannot release it to a customer who asks for support.

Either he is totally ignorance about it or the company has rotten by bureaucracy. :( I wish I didn't write to the company for support so that I wouldn't have to be upset as such.

You can see the post in my blog here.

Thanks again for you guys' help.

Tom Tsui
FSX Times
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From the colours point of view it's even easier than you have said.
All you need to do in fact is to overlay images one on top of the other. And where you need a "window" to see the image below then that part of the overlay is 0,0,0.

In my example overlay 2 is a rotating disc covered by a static mask with a window. The top overlay also has a window that correspondswith the static mask except that that the top overlay rotates as well. The effect being that both windows are aligned only when the valve is open.


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Noted and thanks for the tips.

Basically, I don't have problem with transparency and overlay. Just the mask part. But your example is a good reference indeed.