hey stuart,
a great bunch of tutorials is here at nehe:
http://nehe.gamedev.net
blending:
http://nehe.gamedev.net/da
do you have any specific question?
ike
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Browse All TopicsG'day All,
I'm slowly working my way through tutorials and code trying to get my head around OpenGL. What I am trying to do is program a very simple game:
1. Have an image as a background, for example, a battleground with enemy installations
2. Have the background image obscured by a black veil
3. Be able to paint transparently on sections of the black veil to remove the "fog of war"
4. Transparent sections reveal parts of the battleground, ie the underlying image
My first question: is this scenario possible with OpenGL? My second question: how do I go about doing this?
I am using OpenGL 1.1 and writing the game in C. Most of the tutorials I have been through show how to paint sprites onto a screen, but there's not a lot of attention paid to blending and transparency.
Any help appreciated. Thanks for reading.
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hey stuart,
a great bunch of tutorials is here at nehe:
http://nehe.gamedev.net
blending:
http://nehe.gamedev.net/da
do you have any specific question?
ike
>> My first question: is this scenario possible with OpenGL?
yes
>> My second question: how do I go about doing this?
you have to read a lot of tutorials and books, look at other code and projects .. maybe use external game-librarys, like ogre or others .. and most importantly .. try and error :) make a prototype to validate, whether your ideas work or not ..
that were only general tips, to help you better, we need to know in which part of the project you are stuck..
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by: InteractiveMindPosted on 2009-03-21 at 09:40:53ID: 23947912
Yes, OpenGL is certainly up to the task.
urces/faq/ technical/ transparen cy.htm
You use blending for transparency effects, whereby the alpha component defines the opacity.
See here for an elaboration:
http://www.opengl.org/reso
If you have further questions, let me know..