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I loaded up one of my earlier 3D terrain engines and altered the cloud effect a bit.
Now that I understand more of what is going in during alpha blending and how to create cool DDS textures that make use of it....I can achieve more effects than before.
The sun glare is still not done because it's not quite right yet. It will require some new techniques to get it to look like a flare instead of a billboard behind the clouds.
That looks very nice, keep up the good work.
When doing the alpha blending, are you actually skipping 'alpha pixels', i.e so that like if you wanted to render a fence you would be able to see through the fence where the alpha pixels, but everything else is opaque. I guess that's what you must be doing. I don't know how to do that in OpenGL.
Yes i just took the clouds texture and grey-scaled it. Then I painted in areas of nearly black and smoothed the thing about a trillion times. Then I fired up DX Tex Tool and used the color pic, changed the surface format to A8R8G8B8 and opened the grey-scale texture onto the alpha channel of the final texture. Saved it as a DDS and loaded it in game with D3DXCreateTextureFromFile().
The sun is rendered first and it's y coord is higher than the clouds. Then the clouds are rendered and alpha-blended with what's already in the buffer (namely the sun). I've also chosen a sky color to represent the sky since the sky is no longer a part of the actual texture. The sky is really just the color I clear the render target with but since the clouds are alpha-blended...it looks as though the clouds are moving through the sky.
I will probably add a skybox to produce a gradient sky but right now I'm having problems with mirroring textures on my card. For some odd reason it puts seams at the borders and it shouldn't.
that looks very cool bubbs, I havent done any graphics programming in a while but seeing this kind of thing makes me want to get back to it.
Is this integrated into the voxel terrain you were working on before? I bet that sky would look nice all together with it.
That is just awesome!!!
No this is in the 3D terrain engine. Currently the terrain is not rendered - hence the 250 FPS im getting. I'm re-working the terrain drawing code.
Bubba how long did it take you to get this good, how long have you been programming for, what books did you buy, are you going to release the code for your game it looks amazing and would be helpfull to people learning D3D.
looks rlly good bro, nice job!
looks awesome! i aspire to your greatness
u guys r awsome i wish i knew how to do that
this is a great site but the tutorial dont help me much
Bubba is sick with the game programming!! nice work dude!! ;)
It's a blend mode, so you could doQuote:
Originally Posted by Darkness
glBlendMode(GL_ONE, GL_ONE)
I can't really remember how it's done to be honest, it's been a few months since I wrote any GL stuff. :(
You cannot achieve those effects doing what you just said, but bubba explained it to me anyway.
It also doesn't help that there's no such thing as glblendmode
you probably meant glblendfunc
Here are the textures: I combined these to produce a DDS file in DirectX Texture Tool. You could also just as well use a PNG or any other format that supported alpha channels.
I'm including the alpha channel grey scale here as well as the color bitmap.
Hopefully you can see from this what is taking place.
Remember:
Black - completely transparent
Grey - 50 transparent/50 opaque
White - completely opaque
Here is the color bitmap.
Here is the grey scale alpha channel.
As you can see the angle at which I took the screenshot and the sun angle don't quite match. A lesson to be learned here is that if you produce an image that looks good it just might fool the human eye into believing it's real or somewhat real.
Case in point:
1. There is a line on the right side of the first image. This is a direct result of tiling an image using the mirror function. Obviously my card does not mirror correctly or it is 1 pixel off for some reason which creates nasty blue grid lines.
2. The sky is really just the color I chose to clear the entire buffer with. It just so happens that I matched the color with the color in the pic and since the alpha channel is black in places and grey in others it looks as though the sky is showing through the clouds.
3. The sun is at the wrong angle for the lighting that is on the clouds. Also notice the perspective in the original image. The perspective comes from the picture being taken from the ground lookin up at about 45 degrees or 30 degrees above the horizon. What I really need is a cloud picture taken while looking straight up - thereby allowing me to create the perspective with my 3D engine instead of having the perspective molded into the bitmap.
4. The clouds look like they are at different Y levels above the ground. They are not. Notice the top right cloud and how it is stretched and looks weird? That's because this is a bitmap that is tiled onto a 3D plane - or a 3D square in the sky that represents the sky quad. It is one huge quad. I'm using some tricks with U,V coords to create the tiling and wrapping and such.
5. On the far left side of the image if you look you will see another faint line. Now look on either side of the image and you get a kind of kaleidescope image - the left matches the right exactly. This is because you are looking at about 3 grids of the same cloud image...but they are mirrored.
6. 250 FPS...wow man that's a lot. Yeah and it's also very misleading. There is no terrain in the shot and, in fact, there isn't any terrain being drawn at all. I'm re-working the terrain algo so it is not rendered in this pic, hence the enormous frame rates. No I'm not John Carmack - I won't get any where near 250 FPS when the terrain is drawn....unless my culling algos are perfect.
But none of you seemed to notice. Also be wary of screenshots because I only show you what looks good. Just like the game manufacturers show you screenshots of their game...they only show you the good stuff. They don't show you the ugly clipping/culling errors prevalent in just about every engine out there.
And while we are on the subject of illusions in games, I've also learned from my experience with Joint Ops: Typhoon Rising that AI and graphic engines are not as complete/smart as you think. A lot of it comes from the map maker making the AI 'look smart' by using lots of scripts to encode their actions. Also just from making my own maps and having objects glitch here and there....a lot of care is taken when designing maps and levels not to burden the engine beyond what it can handle...but still present a very good looking level. For instance in JO if you include too many trees...the thing crawls. But you can get the same effect as a dense jungle by using strategic placement of large trees, bushes, etc. I've had objects disappear completely, glitch, and have found objects that you should never use inside of buildings. The engine is not perfect but all the original coop maps and levels are built with all of this in mind so they don't experience the glitching. Overall I'd say that JO is not even 80% finished. There is a lot that has not been done yet.
All of this is simpy an optical illusion.....and it works.
:( I thought it was, but I googled for "glblendmode" just to check and got a load of results. So, blame google. :pQuote:
Originally Posted by Darkness