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Varmint007

Question: Gauge image resolution

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I'm keeping the question vague on purpose because I hope that we can collect tips for gauge images here. I have a few specific questions, but please feel free to add anything you may feel will help not only myself, but anyone who is searching the archives for tips on making good, clear images.My immediate questions:1) I've read that bmp resolution is limited in xml gauges. If this is true, what is the max resolution we can work with?2) I've read that one way to help keep images clear is to make them small and let the sim scale up rather than making them large and scaling down. Apparently, the sim does a far better job of scaling up and keeping things clear than it does of scaling them down and keeping them clear. Is this true?3) If the above about scaling is true, where could we get some good fonts that will look decent at 6-8 pixels? The ones I currently have look horrid until I get them up to about 16.4) I know that bmp's don't have to be limited to 256 colors to work... but that leads me to wonder exactly which formats will and won't work in gauges... DXT3? 888? Others?5) Translucency... I've tried the tutorial that's posted on alpha channels and, oddly enough, it worked great as far as my editors could tell but when I loaded it into FS9 or imagetool the alpha info was ignored completely. So, I re-opened it in the editor to see what happened and the editor displayed it perfectly, with alpha. The alpha channel was added by using imagetool from the command line, as is recommended in the tute. Any tips on what may have gone wrong or other ways to achieve 75%, 50%, 25% alpha, etc. would be appreciated.That's all I can think of for now. Please feel free to add any tips about making good images for gauges and panels that you may want to share, even if they have nothing to do with the original questions.Thanks,Scott / Vorlin

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>I'm keeping the question vague on purpose because I hope that>we can collect tips for gauge images here. I have a few>specific questions, but please feel free to add anything you>may feel will help not only myself, but anyone who is>searching the archives for tips on making good, clear images.>>My immediate questions:>>1) I've read that bmp resolution is limited in XML gauges. If>this is true, what is the max resolution we can work with?It is true, although I can't give you an exact dimension. I've had trouble with bitmaps in the 1600 pixel range and I've had trouble lower than that. My best advice would be to avoid bitmaps if at all possible and think about using vectors instead. If you must use very large bitmaps, then there's probably a way to piece together several smaller ones and translate/rotate them separately.What happens with large bitmaps is undesirable artifacts can show up and scintillate at various resolutions, or may simply fail to draw.>2) I've read that one way to help keep images clear is to make>them small and let the sim scale up rather than making them>large and scaling down. Apparently, the sim does a far better>job of scaling up and keeping things clear than it does of>scaling them down and keeping them clear. Is this true?I agree with that. If you design small (and this assumes vectors and/or fonts, not bitmaps), then you can control the display much better. This way all your geometry can be designed at the lowest common denominator (i.e. 800x600). If it looks good there, it'll look much better at higher resolutions. It's much harder to design at a higher resolution and achieve good text/graphics placement when scaled down. I learned that the hard way after designing hundreds of gauge elements at a large size only to find they were unreadable when testing at lower resolutions.One caveat: With BITMAPS, such as those used for 2D panels, it's better to start with the HIGHEST resolution (i.e. designed for 1600x1200 panels) and let the sim scale them down. Reason being they will look much better at high resolutions and will look comparable to native (smaller) images when scaled down. The penalty here is the extra memory usage, but it should be neglidgeable for most panels.>3) If the above about scaling is true, where could we get some>good fonts that will look decent at 6-8 pixels? The ones I>currently have look horrid until I get them up to about 16.I assume there are some out there, but I don't know of a specific source. I use an inexpensive font program called Font Creator to design my own. 6 point is pushing it, however.>4) I know that bmp's don't have to be limited to 256 colors to>work... but that leads me to wonder exactly which formats will>and won't work in gauges... DXT3? 888? Others?In gauges I'm fairly sure you're limited to 8/24/32 bit. I don't think any extended bitmaps will display in a gauge, however it's been a long time since I crossed that bridge.>5) Translucency... I've tried the tutorial that's posted on>alpha channels and, oddly enough, it worked great as far as my>editors could tell but when I loaded it into FS9 or imagetool>the alpha info was ignored completely. So, I re-opened it in>the editor to see what happened and the editor displayed it>perfectly, with alpha. The alpha channel was added by using>imagetool from the command line, as is recommended in the>tute. Any tips on what may have gone wrong or other ways to>achieve 75%, 50%, 25% alpha, etc. would be appreciated.Are you converting the alpha images to 8-bit with alpha for use in gauges? Also, Imagetool can misinterpret all black or all white alpha channels as empty. Download and use DXTBmp instead. It's much more flexible, although it will require a little bit of configuration (I think it generates and saves MIPs by default. --Jon

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Jon,Thanks for the information! You answered most of my questions but I think I wasn't clear enough on some things:>>1) I've read that bmp resolution is limited in XML gauges.>If>>this is true, what is the max resolution we can work with?>It is true, although I can't give you an exact dimension. I've>had trouble with bitmaps in the 1600 pixel range and I've had>trouble lower than that. When I spoke of resolution I meant in dpi, not overall size. I'm already constructing everything in small pieces. What I'm wondering is what is the max dpi we can author in? 72? 96? 360? Obviously, the higher we can go, the sharper our originals will be... then they should display at whatever dpi the monitor is set at. Designing in 360dpi and displaying on a 96dpi monitor should look good but designing in 72dpi for the same monitor can look horrid, especially when the sim starts scaling things. I'm wondering how high we can take the dpi when authoring bmp images?Also, what do you mean by vectors? I'm well versed in FlashMX and use vector graphics in it, but I know of no way to do anything similar in XML. If I use Flash to author images for FS9, I've had to export and convert to bmp, but I don't think that's what you're referring to when you refer to vectors in your reply above.>>2) I've read that one way to help keep images clear is to>make>>them small and let the sim scale up rather than making them>>large and scaling down. Apparently, the sim does a far>better>>job of scaling up and keeping things clear than it does of>>scaling them down and keeping them clear. Is this true?>I agree with that.... (snipped to keep this reply a reasonable length).>>One caveat: With BITMAPS, such as those used for 2D panels,>it's better to start with the HIGHEST resolution (i.e.>designed for 1600x1200 panels) and let the sim scale them>down. Reason being they will look much better at high>resolutions and will look comparable to native (smaller)>images when scaled down. The penalty here is the extra memory>usage, but it should be neglidgeable for most panels.The problem I've been having is that I author a bmp at, say, 300x300 and when the sim scales it down, all the edges blur. So far, I've been working in 72 dpi... which I think may be a large part of the problem. This is what lead to my question about dpi above.>>4) I know that bmp's don't have to be limited to 256 colors>to>>work... but that leads me to wonder exactly which formats>will>>and won't work in gauges... DXT3? 888? Others?>In gauges I'm fairly sure you're limited to 8/24/32 bit. I>don't think any extended bitmaps will display in a gauge,>however it's been a long time since I crossed that bridge.I notice that you didn't list 16 bpp... an oversight? If we can use 16 bpp, we can achieve just about anything we need.>>5) Translucency... >Are you converting the alpha images to 8-bit with alpha for>use in gauges? Also, Imagetool can misinterpret all black or>all white alpha channels as empty. Download and use DXTBmp>instead. It's much more flexible, although it will require a>little bit of configuration (I think it generates and saves>MIPs by default. I have DXTBmp and use it for aircraft repaints. I can't seem to get it to save in shades of alpha... either it's transparent or it's opaque. Also, it seems to resize some images at times instead of maintaining the original size. I may have to research more on advanced uses of DXTBmp, because you seem to imply that it could meet my needs when it comes to various degrees of opacity.Thanks for the info Jon! And, once again, that is a KILLER VC you're working on!Scott / Vorlin

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>When I spoke of resolution I meant in dpi, not overall size.>I'm already constructing everything in small pieces. What I'm>wondering is what is the max dpi we can author in? 72? 96?>360? Obviously, the higher we can go, the sharper our>originals will be... then they should display at whatever dpi>the monitor is set at. Designing in 360dpi and displaying on a>96dpi monitor should look good but designing in 72dpi for the>same monitor can look horrid, especially when the sim starts>scaling things. I'm wondering how high we can take the dpi>when authoring bmp images?Well again, this goes back to what I said about starting with images designed to display at 1600x1200 (realistically the highest 4:3 resolution anyone is likely to play in for the foreseeable future). The actual DPI you save your work in is irrelevant since the sim is only concerned with the pixel volume of the image at 72DPI. You could make 2 images both 1600x1200, one at 72DPI and one at 300DPI, and they would look identical in flightsim assuming the higher resolution image would even display.It's also important to note that you'll never be able to please all the people, all the time. If a user has a wide-screen display (becoming more and more popular as LCD prices fall), you're just screwed. The 2D art is going to look bad and there's no way around it. It'll be scaled horizontally and vertically to resolutions that just aren't 4:3. The only way you can deal with that situation is via the VC. The user most likely had no idea this was going to happen when they made their decision to go wide-screen, but you can't do anything about it.>Also, what do you mean by vectors? I'm well versed in FlashMX>and use vector graphics in it, but I know of no way to do>anything similar in XML. If I use Flash to author images for>FS9, I've had to export and convert to bmp, but I don't think>that's what you're referring to when you refer to vectors in>your reply above.By vectors, I mean any graphic element (lines, polygons, circles) or text which is not a bitmap.>The problem I've been having is that I author a bmp at, say,>300x300 and when the sim scales it down, all the edges blur.>So far, I've been working in 72 dpi... which I think may be a>large part of the problem. This is what lead to my question>about dpi above.You can't avoid scaling, but you can choose the lesser of two evils by letting the sim scale down instead of up. I don't see much point in authoring at any resolution other than 72DPI. Since pixel coodinates are such an integral part of panel design, you'll only make trouble for yourself down the road by having to convert between 72DPI and some other density.>>In gauges I'm fairly sure you're limited to 8/24/32 bit. I>>don't think any extended bitmaps will display in a gauge,>>however it's been a long time since I crossed that bridge.>>I notice that you didn't list 16 bpp... an oversight? If we>can use 16 bpp, we can achieve just about anything we need.Flightsim will convert any image to 24 bit in memory, but 8-bit images are likely to load faster. 32 bit images are simply 24 bit images with alpha, but I think you need to use only 8-bit with alpha for 2D panel work. I seem to remember that Flightsim will not accept 16 bit images.--Jon

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