OpenGl and selective drawing

[User137]

There is 1 other "feature" that is caused by linear filtering... Imagine your tilemap texture like this:

RRRRWWWWRRRR
RRRRWWWWRRRR
RRRRWWWWRRRR
RRRRWWWWRRRR
RRRRRRRRRRRR
RRRRRRRRRRRR
RRRRRRRRRRRR
RRRRRRRRRRRR

...where R is red pixel and W is white, and pattern size is 4x4. Now if you draw pattern 1 which is full W, it will show red borders to it.

This can be fixed by for example leaving a empty transparent black line between each tiles.
Or skipping half pixel length from the texture coordinates at borders.

Oh, and 2739x2264 will not most likely work on most graphics cards, my own to name 1 (Radeon HD 5770). Texture width and height must be power of 2, for example 512 x 1024, it doesn't have to be square.