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View Full Version : GL_BLEND killing my little app performance? Is this right?



10-31-2000, 11:12 AM
I have a little app using lighting + depth test + textures then I added some blending function only to draw 3 semi-transparent quads. At a start I had 270 fps, if I only enable GL_BLEND it get down to 250. If I draw 1 quads using blending it gets down to 200, and with the 3 quads at the same time it gets to 94 fps! Is this normal? How can I optimize this?

Hardware: Pentium !!! 600, Winfast Geforce 256.

Glenn Upton
10-31-2000, 06:45 PM
Is normal but does not matter. Your application may draw 200+ fps but your monitor only displays less than 100 per second (actual depends on monitor). So you are drawing frames that never get displayed. Somewhere around 60-70fps is optimal cause most modern monitors can handle that. Much more than that is irrelevant.

zed
10-31-2000, 11:45 PM
it depends on how large the quads are big ones are gonna eat up a lot of fillrate

11-01-2000, 05:40 AM
Im currently using blending to draw a big background (1 non blended image + 3 layers of clouds). It has the same width and height that the current viewport. So, you think is normal? Is there a better way of doing this? Thanks