Author Topic: [Solved] Unwanted pixels showing up... (Read 3375 times)

Phoenixangel · « **on:** June 24, 2008, 12:43:34 am »

An image is still worth a thousand words, right? ^_^'

I would like to know why I get those ugly unwanted pixels... and how to get rid of them

I loaded my images from BMP with a fuschia background
CreateMaskFromColor(sf::Color(255,0,255,255), 0)
then, I made my sprites from the modified images

I also tried to use PNG with an already transparent background but it did the same...

NewbiZ · « **Reply #1 on:** June 24, 2008, 01:51:19 am »

Right after the loading of your image:

Code: [Select]

image->SetSmooth( false );

Phoenixangel · « **Reply #2 on:** June 24, 2008, 02:02:01 am »

thanks ^^

quasius · « **Reply #3 on:** June 24, 2008, 06:13:22 am »

Another solution that preserves the pixel smoothing is to use a source image that has a "border" of correct-color pixels around the actual sampled area. What's happening is OpenGL is trying to apply a linear interpolation filter to your sprite that's grabbing the pixel neighbor of each pixel. If the border pixel is fuschia, you'll get the artifacts you're seeing.

acrin1 · « **Reply #4 on:** June 27, 2008, 01:51:02 pm »

Quote from: "Phoenixangel"

I would like to know why I get those ugly unwanted pixels... and how to get rid of them

Apologies as this is not strictly speaking an SFML query but I have the same problem described above with the OpenGL part of my SFML program and wondered if someone could suggest any obvious changes as there are obviously quite a lot of experienced SFML/OpenGL users here:

The arch in the screenshot is a transparent PNG rendered as a quad but I get a flickering artifact line running along the bottom of the quad depending on the position of the quad. Are there any obvious OGL settings I should investigate? (I'm trying to re-create the original game hence the "flat" arch rather than a real 3D arch model).

Many thanks.