Alpha Channels

[greatflash]

Been working on a new theme and decided to re-do all icons (mame, all emulators, GameEx standard, etc). What i have noticed is an error in the way transparencies are handled.

I always make the graphics as 16bit RGBs saved as PNG with transparent backgrounds (have also tried with Solid black non transparent) and have noticed that either depending on the colours (colors - for our American friends ) used or the jaggyness of the outline, I still get black areas. This can be shown by making a icon with a large feathered edge, when shown in GameEx the feathered edge becomes black (this also happens with shadows). This also affects smooth anti-alias edges, but why some look ok and some have nasty black bits, it have no idea??

Any help would be VERY welcome! Is this a problem with the rendering in GameEx, or am I a complete knob?

Included 2 examples

EX1 shows some signs and EX2 shows it in the icons top right!

[iano]

Been working on a new theme and decided to re-do all icons (mame, all emulators, GameEx standard, etc). What i have noticed is an error in the way transparencies are handled.

I always make the graphics as 16bit RGBs saved as PNG with transparent backgrounds (have also tried with Solid black non transparent) and have noticed that either depending on the colours (colors - for our American friends ) used or the jaggyness of the outline, I still get black areas. This can be shown by making a icon with a large feathered edge, when shown in GameEx the feathered edge becomes black (this also happens with shadows). This also affects smooth anti-alias edges, but why some look ok and some have nasty black bits, it have no idea??

Any help would be VERY welcome! Is this a problem with the rendering in GameEx, or am I a complete knob?

Included 2 examples

EX1 shows some signs and EX2 shows it in the icons top right!

Flash, i'm exactly sure what you're talking about (i don't know anything about gfx) but i think Adultery had a similar problem with his 'M' logos and Headkaze provided the solution. Read the thread - see if it's what you're looking for.

http://www.gameex.info/forums/index.php?sh...t=0&start=0

[Tempest]

Been working on a new theme and decided to re-do all icons (mame, all emulators, GameEx standard, etc). What i have noticed is an error in the way transparencies are handled.

I always make the graphics as 16bit RGBs saved as PNG with transparent backgrounds (have also tried with Solid black non transparent) and have noticed that either depending on the colours (colors - for our American friends ) used or the jaggyness of the outline, I still get black areas. This can be shown by making a icon with a large feathered edge, when shown in GameEx the feathered edge becomes black (this also happens with shadows). This also affects smooth anti-alias edges, but why some look ok and some have nasty black bits, it have no idea??

Any help would be VERY welcome! Is this a problem with the rendering in GameEx, or am I a complete knob?

Included 2 examples

EX1 shows some signs and EX2 shows it in the icons top right!

Your a complete Knob! :LOL

I'm just glad to see you've been busy...I thought for sure you had been banned!

Unfortunately, I don't know anything about Graphics either...Sorry!

[fRequEnCy]

It's the way GameEx handles transparencies. headkaze explains here

[greatflash]

Your a complete Knob! :LOL

I'm just glad to see you've been busy...I thought for sure you had been banned!

Unfortunately, I don't know anything about Graphics either...Sorry!

Yep - Still here

Been working on the Computer Snaps for Circo... Doing 3 sets at once as doing just one gets quite boring!

Was just trying to tidy up the icons on the theme I made.. Still getting no-where!! Bugger!

[greatflash]

It's the way GameEx handles transparencies. headkaze explains here

Thanks, checked that out and it does not really solve the problem. As I said in original post, I have tried the Black method, but smooth gradients become black areas. It is a shame!

Would be great if GameEx could handle true transparancies rather than using black as a mask!

Perhaps I could try bribing Tom again

[greatflash]

Flash, i'm exactly sure what you're talking about (i don't know anything about gfx) but i think Adultery had a similar problem with his 'M' logos and Headkaze provided the solution. Read the thread - see if it's what you're looking for.

http://www.gameex.info/forums/index.php?sh...t=0&start=0

Thanks for the reply. The link was of a help, but i am afraid offered no real solution..

Oh well.. Getting too tired now - will fiddle again later!

Cheers

[fRequEnCy]

Thanks, checked that out and it does not really solve the problem. As I said in original post, I have tried the Black method, but smooth gradients become black areas. It is a shame!

Would be great if GameEx could handle true transparancies rather than using black as a mask!

Perhaps I could try bribing Tom again

Yeah I have a few icons that do that due to drop shadows in them. Only solution for me was to cut all drop shadows out and use the polygon lasso tool to cut out my images instead of the wand tool. Would be nice if it could just handle it the way we like. Let's see if your bribe gets Tom to do it.

[greatflash]

Yeah I have a few icons that do that due to drop shadows in them. Only solution for me was to cut all drop shadows out and use the polygon lasso tool to cut out my images instead of the wand tool. Would be nice if it could just handle it the way we like. Let's see if your bribe gets Tom to do it.

I have cut mine manually and avoided magic wand etc. The look great if composited on a background for gameex but get black bits when used to overlay as icons. I am sure GameEx only used black as a mask, and does not make use of the 256 bits of the alpha channel!!

[greatflash]

TOM - if you are reading this, I am offering another one of those Flash bribes again

At least, let us know if this is something you are likely to impement on V3 themes?

Failing that - would love to click that donate button again

[headkaze]

The problem is the GameEx video system is using DirectDraw which does not support alpha channel only color keying a single color. Unless Tom rewrites the entire video system for Direct3D alpha channel will never be supported.

[greatflash]

The problem is the GameEx video system is using DirectDraw which does not support alpha channel only color keying a single color. Unless Tom rewrites the entire video system for Direct3D alpha channel will never be supported.

I thought DirectX supported alpha channels? If it does not then that is a real shame! How does other media centre software manage to do it? Oh well.. Not to worry, would have been nice to get them to look more professional. The only other way is to convert them to indexed colour. This stops the black bits appearing (kill shadows etc though) but has the down side that any curves no-longer have anti-aliased edges, cause quite apparent stepping.

[greatflash]

Tom is a clever puppy and I have a feeling that he may be working on some of this for the V3 themes. It was mentioned that he wanted a more media centre look! I will keep my fingers crossed.

In the meantime, I have found a solution. I put cooking oil on me glasses and the black bits magically vanish. Well... So does everything really, It's a semi-work-around.

[bkenobi]

Beer does the same thing and doesn't require cleaning your glasses!

[Tempest]

Hey you two...no joking around in the forums!

Didn't you get the memo?

[greatflash]

Hey you two...no joking around in the forums!

Didn't you get the memo?

I wasn't messing about - i went as far as to say Tom was a clever puppy.. See - I CARE...

Seriously though - It would be really nice to have true alpha channelled icons. Would make it look A LOT classier. WDYT?

[Tom Speirs]

Thanks, checked that out and it does not really solve the problem. As I said in original post, I have tried the Black method, but smooth gradients become black areas. It is a shame!

Would be great if GameEx could handle true transparancies rather than using black as a mask!

Perhaps I could try bribing Tom again

Unfortunatly bribes arnt going to help here. Its just a drawback of the display libraries GameEx uses as HK explained. I have been thinking about moving to Direct3d and I would like to but its a lot of work for very little benefit.

PS: Sorry about the ticking off the other day. I was obviously having an anal retentive moment. It happens

[greatflash]

Unfortunatly bribes arnt going to help here. Its just a drawback of the display libraries GameEx uses as HK explained. I have been thinking about moving to Direct3d and I would like to but its a lot of work for very little benefit.

PS: Sorry about the ticking off the other day. I was obviously having an anal retentive moment. It happens

That is a real shame it is so hard to implement! I believe it would be a really nice addition. Is there any other way to avoid the black stepping on anti-aliased areas on my icons, either from the gameex end or from my end with the way i do them?

i could up the bribe

BTW - Tempest keeps messing about on the forum, i am a bit scared to tell him off though, perhaps.......

Nice to hear from you anyway. Will clean my glasses and accept it - sniff!

[bkenobi]

One way would be to include a clip of the background in the image. Use Photoshop (or whatever) to alpha blend the images and then save them with a solid background. You would have to be VERY careful of where the image was located to avoid mismatches if you don't use a solid background though.

This isn't as easy as blending, but it could work and give you the same effect.

[greatflash]

One way would be to include a clip of the background in the image. Use Photoshop (or whatever) to alpha blend the images and then save them with a solid background. You would have to be VERY careful of where the image was located to avoid mismatches if you don't use a solid background though.

This isn't as easy as blending, but it could work and give you the same effect.

That is a very good idea and worth a try. Thanks for that!

Tempest - you let me down

[bkenobi]

HA ha

[Tempest]

That is a very good idea and worth a try. Thanks for that!

Tempest - you let me down

Hey, I could have chipped in with another wrong answer, but I honestly don't do it on purpose...not even for you.

Is that avatar really you? I just think it's odd that BK had to say something to you about beer, when you already had one in your hand.

BTW: Bkenobi - at least I was right about that Andrea chick!

[greatflash]

That is a very good idea and worth a try. Thanks for that!

Tempest - you let me down

Tried it for the last 2 hours..

Sort of works. My snap size is 700x700 located at 80,240. If i select that area from the background and save it as one of the emu icons, when that icon is selected the 700x700 pic is overlaid on the background.. But... It is slightly transformed, seems off by 1 pixel at top and left and shrunk by 2 pixels on the right and base. Have tried for ages to correct this, to no avail. I have noticed a slight error before. The starback.png and custom emu backgrounds are not rendered the same. If i keep them the same size (1920x1200 in my case), the emubacks are squashed slightly (noticable if using the same pattern on them). I had to reduce (crop not resize) the emubacks to 1917x1197 (3 pix) to get them to display exactly the same as startbak.? Hope that makes sense. Perhaps the same sort of thing happens with the icons?

Who knows - i think i have had enough of this concentrating stuff now. Some of my brain has seeped out me ear and one of my eyes fell out and marked the monitor.. oh well, such is life

[greatflash]

Hey, I could have chipped in with another wrong answer, but I honestly don't do it on purpose...not even for you.

Is that avatar really you? I just think it's odd that BK had to say something to you about beer, when you already had one in your hand.

BTW: Bkenobi - at least I was right about that Andrea chick!

Yes it is me?? sorry for puting a REAL pic up! hope it does not give you nightmares. I can do that to people, the wife makes me sleep in the cupboard with the broom and mop. Good old Mr. Broom. Much better than that nasty Mrs Mop - she picks on us...

[bkenobi]

Yeah, I figured that might be a problem. Matching the background is going to be tough unless you can get some kind of input from HK and/or Tom on the logic used to locate the image. I don't know if it will ever be "perfect", so unless you have a solid background, this workaround is mediocre at best.