Tagged Questions
1
vote
0answers
49 views
How to put OpenGL in a state for drawing blended, colored, nontextured polys?
Using OpenGL1.1 (sadly) I'm trying to draw a cube, which is colored and alpha blended. It is instead showing up as opaque black. Even without including alpha in the color it still shows up as opaque ...
5
votes
1answer
211 views
What are the rest of the blending functions used for?
In general, I know of five ways to make use of blending functions (these are for OpenGL, but replace glBlendFunc() with SetRenderState(D3DRS_SRCBLEND) and SetRenderState(D3DRS_DESTBLEND) for DirectX):
...
0
votes
1answer
125 views
Artifacts when draw particles with some alpha
I want to draw in my game some particles. But when I draw one particle above another particle, alpha channel from this above "clear" previous drawed particle.
I set in OpenGL blend in this way:
...
0
votes
1answer
175 views
Rendering two textures with blending and alpha test
What I am looking for is the following: I have a circle on a square image, alpha is 0 at the corners
and also a square shadow, alpha is 0 everywhere else
I would like to have as final result a ...
1
vote
1answer
848 views
Understanding how OpenGL blending works
I am attempting to understand how OpenGL (ES) blending works. I am finding it difficult to understand the documentation and how the results of glBlendFunc and glBlendEquation effect the final pixel ...
2
votes
0answers
212 views
AlphaToCoverage + Alpha Blending = Artifacts
I'm experiencing a strange problem using OpenGL SampleAlphaToCoverage mode. There are rendering artifacts when using alpha-blending on pixels that have been rendered using alpha-to-coverage - and I ...
25
votes
5answers
5k views
How can I achieve a good fire effect with alpha blending and particles?
Using the following setting for the OpenGL particle effect:
SRC: GL_SRC_ALPHA
DST: GL_ONE
Creates an additive blend, which looks spectacular on a black background but terrible on brighter colours, ...
1
vote
1answer
427 views
How can I implement “cut outs” for lighting in OpenGL?
So, I'm working with OpenGL (I'm not exactly sure of the version), and I want to do an old-style lighting setup by essentially drawing a black rectangle over the screen, and drawing white circles over ...
2
votes
2answers
1k views
blending alpha textures in gluOrtho2D
i'm doing a simple game/application with some minimal 2d graphics: png textures and ploygons with standard glVertex calls
my setting:
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0, w, ...
7
votes
2answers
4k views
How do I use depth testing and texture transparency together in my 2.5D world?
Note: I've already found an answer (which I will post after this question) - I was just wondering if I was doing it right, or if there is a better way.
I'm making a "2.5D" isometric game using OpenGL ...
4
votes
2answers
1k views
Blending 2d images to subtract alpha
I'm looking into doing a 2d lighting system with a result similar to this: http://forums.tigsource.com/index.php?topic=15619.0 This thread I believe disregards color, as well as doesn't really list a ...
