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Im currently making a demo, but Im having a lot of trouble getting it to fade in/out of black. Ive tried giving the whole scene an alpha value and slowly increasing that ... but it just appears like normal. Ive tried blending a black quad over the entire scene and changing its alpha value and still no luck. Anyone care to enlighten me as to what im doing wrong... I am probably not blending the quad properly or somthing like that. Thanks in advance... i can post some of the code if need be

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One option (not the best) is to use the imaging extention. It has a brightness control. But stay away from extentions whenever possible. I have always used the black quad like you said, it should by all means work. Show some code and I may be able to spot your problem.

A-Tronic Software & Design
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"if you fail in life, you were destined to fail. If you suceed in life, call me."

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	if (morphin == true)	{		glLoadIdentity();		glTranslatef(0,0,-10);		glBlendFunc(GL_SRC_ALPHA,GL_ONE);		glEnable(GL_BLEND);						// Enable Blending		glColor4f(0,0,0,morphval);		glDisable(GL_DEPTH_TEST);		glDisable(GL_LIGHTING);		glBegin(GL_QUADS);			glVertex3f(-500,500,0);			glVertex3f(500,500,0);			glVertex3f(500,-500,0);			glVertex3f(-500,-500,0);		glEnd();		morphval -= 0.01f;		if(morphval <= 0)		{			morphin = false;		}		glDisable(GL_BLEND);		glEnable(GL_DEPTH_TEST);		glEnable(GL_LIGHTING);	}

Thats what I have now... I tried a bunch of other ways... like without disabling lighting and depth testing ... but that did nothing...

Thanks again

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First off, I assume this is being called at the end of the draw code, as it disables depth testing. Second, try using

glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

Um, I think that''s right. Lemme know.

A-Tronic Software & Design
-----
"if you fail in life, you were destined to fail. If you suceed in life, call me."

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Thanks allot that was exactly what i was looking for!

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For a black quad, you can use GL_ZERO, GL_ONE_MINUS_SRC_ALPHA or even GL_ONE, GL_SRC_ALPHA (and then think of the source alpha as a brightness for your background--ie. 0 = totaly black, 1 = totally white). The GL_ZERO means that no source color info is used. I would hope GL_ZERO would skip some math in the blend routine, but I dunno.

Just some additional info to confuse you.

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I''m also puzzling with a fade to black effect. I basically have the same code as above with

glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

my problem is that as soon as i start drawing the fade , so alpha would be 0. The screen looks darker.but with a alpha of 0 i should see the normal screen?

This annoys me since there is a jump in my fade. It looks ok but it''s not what i want ;-)

i didn''t disable lighting, hope that''s going to help

-Airo

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Have a look at my demo''s source (CrystalTears).. I have some routines to fade in/out screen with quads...

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Thanks i''ll do that.

By the way do you have crystal tears working for w98 se?

Cause i''m still curious how it looks

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Not yet.. someone mailed me that the only thing he needed to change was timer functions to make it work... bu he didn''t sent me the modyfied code yet.

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