Re: Textures and Masking

Hi,

I haven't checked your Blending so far. But one quite good method is simple multitexturing with the right Texture-Combine Mode. This is independent from what is in the frame buffer before, not like Blending.

Just google'ing a bit should help. (And on modern Graphic Cards at least 4 Texture Units are supported).

For Blending check your 2 images. Like in Nehe said: " It's also very important that your image has a BLACK background and the mask has a WHITE background!".

Maik Wagner


Latti wrote:
I have 2 textures and would like to use 1 texture (black-gray-white) as a Mask for the other (Color). I used the technique described in Lesson 20 of Nehe (http://nehe.gamedev.net/data/lessons/lesson.asp?lesson=20).

The result is not quite what I expected (http://users.pandora.be/bart.de.lathouwer/mask.gif).
I expected the color texture to be only partially visible (where the Mask color is black), in stead, the Mask texture shines through.

Any help anyone?

Thanks
- Bart


glEnable(GL_BLEND);
glDisable(GL_DEPTH_TEST);

glBlendFunc(GL_DST_COLOR,GL_ZERO);
        m_pMaskTexture->Draw(); // glBind and draw GL_QUADS

glBlendFunc(GL_ONE, GL_ONE);
        m_pFrame->Draw(); // glBind and draw GL_QUADS

glEnable(GL_DEPTH_TEST);
glDisable(GL_BLEND); 


.

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