OpenGL Multitexturing Details w/Alpha

WakingJohn

Unregistered

Post: #16

Nov 30, 2004 — 04:15 AM

Again, thanks for all the help. I hope I can repay it one day somehow either to this community or to you =-).

Thanks a million - you made my day... err no - month =-D

WakingJohn

Unregistered

Post: #17

Nov 30, 2004 — 04:54 AM

Seems I spoke too soon -

The base isn't drawing where the details aren't.

Meaning the base is also using the details alpha.

If you need a screen of this i can p rovide one

WakingJohn

Unregistered

Post: #18

Nov 30, 2004 — 05:00 AM

Err wait - I'm going to try a forth pass, interpolate of colormap and colormap in respect to alpha

WakingJohn

Unregistered

Post: #19

Nov 30, 2004 — 05:36 AM

Code:

                    glActiveTextureARB( GL_TEXTURE2_ARB );//detail - instead of pass through, interpol with tex0 in respect to 1-alpha

                     glEnable(GL_TEXTURE_2D);                

                     BindTexture(details);

                     /*glTexEnvi (GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE);

                      glTexEnvi (GL_TEXTURE_ENV, GL_COMBINE_RGB_EXT, GL_REPLACE);

                      glTexEnvi (GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_PREVIOUS);*/

                      glTexEnvi(GL_TEXTURE_ENV,GL_COMBINE_RGB_ARB,GL_INTERPOLATE_ARB); 

                     glTexEnvi(GL_TEXTURE_ENV,GL_SOURCE0_RGB_ARB, GL_PREVIOUS ); 

                     glTexEnvi(GL_TEXTURE_ENV,GL_OPERAND0_RGB_ARB,GL_SRC_COLOR); 

                     glTexEnvi(GL_TEXTURE_ENV,GL_SOURCE1_RGB_ARB, GL_TEXTURE0  ); 

                     glTexEnvi(GL_TEXTURE_ENV,GL_OPERAND1_RGB_ARB,GL_SRC_COLOR); 

                     glTexEnvi(GL_TEXTURE_ENV,GL_SOURCE2_RGB_ARB, GL_TEXTURE1);

                     glTexEnvi(GL_TEXTURE_ENV,GL_OPERAND2_RGB_ARB,GL_ONE_MINUS_SRC_COLOR);

That should work right? (replacing the old tu2)

WakingJohn

Unregistered

Post: #20

Nov 30, 2004 — 07:16 AM

glBlendFunc(GL_SRC_ALPHA, GL_SRC_ALPHA);
makes it visible now, but the details are MUCH too light ( I switched to a GL_MODULATE for the details since its the actualy effect I want, not GL_ADD_SIGNED)

arekkusu

Sage

Posts: 1,231
Joined: 2002.10

Post: #21

Nov 30, 2004 — 03:21 PM

You don't need to enable blending for multitexturing, unless you intend for the final combined texture to be translucent (usually not, for terrain.)

WakingJohn

Unregistered

Post: #22

Dec 1, 2004 — 12:14 AM

Hmm, well see, since I'm using multiple textures, and the DOT3 hack wont work for me, I have to make like 3-4 passes. I can't figure out how to do this otherwise since in my TU1 I need to references the previous and previous only grabs the previous tu

WakingJohn

Unregistered

Post: #23

Dec 4, 2004 — 10:52 AM

I ended going up with this as it was "close enough". The tool is for Myth III: The Wolf Age. Here are the results of the multitexturing on one of the standard maps:

Before: Pepper Heights
After: Pepper Heights
After: Pepper Heights Close up
After: Llanc Close Up Road

Its still not quite right (It actually brightens when there is white instead of darkens... hmm...) but I think it will work for its purpose (which is seeing how things look in a rough fashion without switching to the engine every 5 minutes).

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