not pixel perfect

[99p]

plz see screenshots. this rectb and circb, looks not good.
I use win10, python3.6.2, 1920x1080 display resolusion.
no change in fullscreen(alt+enter).

[Stenodyon]

I'm having the same problem.

Sample program showcasing the bug:

import pyxel

class App:
    def __init__(self):
        pyxel.init(160, 128)
        pyxel.run(self.update, self.draw)

    def update(self):
        pass

    def draw(self):
        pyxel.cls(0)
        pyxel.rectb(20, 20, 100, 100, 7)

App()

Same effect with rect, blt or cls, the last pixel column is not drawn.

Linux Debian 9, python 3.5.3

[carlsmith]

The code @Stenodyon posted is working perfectly for me.

• pyxel 0.7.2
• python 3.7.0
• macOS 10.13.6

[golebiewsky]

The code posted by @Stenodyon works for me on:

• pyxel 0.7.0
• Python 3.7.0
• Windows 10 (1803)

But here:

import pyxel

class App:
    def __init__(self):
        pyxel.init(160, 128)
        pyxel.run(self.update, self.draw)

    def update(self):
        pass

    def draw(self):
        pyxel.cls(0)
        pyxel.rectb(0, 127, 20, 116, 7)
        pyxel.rectb(0, 127, 20, 120, 3)

App()

It shows only first rectangle and I have no idea why, maybe it is related.

[ghost]

Hello,

My setup is the following:

• Pyxel 0.7.3
• Python 3.6.6
• Arch Linux

The examples 03_draw_api.py and 04_sound_api.py shows the same bug as @ponponboy.

04_sound_api.py segfaults right after being launched.

The two test codes by @Stenodyon and @golebiewsky show incorrect behaviour.

Since @carlsmith and @golebiewsky report no incorrect behaviour for the built-in example while using Python 3.7.0, I'll wait for Arch Linux to update Python from 3.6.6 to 3.7.0 before drawing any conclusion.

Screenshots

03_draw_api.py

04_sound_api.py

Test code from @Stenodyon

Test code from @golebiewsky

[carlsmith]

I tried @golebiewsky's code, and it works fine for me (same specs as my last post).

[kev-inn]

I got an pixel-error dependant on the screen size set in pyxel.init()

import pyxel

class MyGame:
    def __init__(self):
        pyxel.init(100,100)
        self.x = 0
        pyxel.run(self.update, self.draw)

    def update(self):
        self.x = (self.x + 1) % pyxel.width

    def draw(self):
        pyxel.cls(0)
        pyxel.rect(self.x,0,self.x+7,7,9)

MyGame()

this code leads to this result:

but if I change the pyxel.init() to

pyxel.init(100,101)

the result is fine:

• Win10,
• Python 3.6.2
• pyxel 0.7.4

[kitao]

Pyxel uses the point sprites of OpenGL to improve the rendering performance.
And rendering area for each drawn object is specified as the size of point sprites.

So I think this bug is caused by the difference of OpenGL implementation.

[kitao]

I will write a bit more.

Pyxel draws each element as point sprite of OpenGL. And to improve rendering performance, rendering area of each element is specified as the size of point sprite.
For examples, if the type of an element is pix, the size will be set as 1. In the case of rect, if the size of it is 40x30, the size will be set as 40 because allowed point sprite shape in OpenGL is only square.

So regarding this bug, it seems that some environment (depends on graphics driver?) decrease the point sprite size by 1. So pix and the longer edge of rect are not drawn.

For now, I don't have smart idea to fix this. Does anyone have good idea?

[kitao]

Can anyone who faces this bug try to change the shaders.py l.54 from gl_PointSize = 1.0; to gl_PointSize = 1.1; and run the example #3 (draw api sample)?

I would like to know the pix api works or not by this change.

[kitao]

Maybe I fixed this bug in 0.7.6.
Can anyone try it out?

Specifically, I changed the rendering position of each element by 0.5 pixel in OpenGL shader.
As a result of it, the edge region should also be treated as pixels regardless of environment. Probably.

[Stenodyon]

0.7.6 fixed the bug for me, thanks!

[kitao]

Thank you for checking it!

[ghost]

I confirm that, on my setup, release 0.7.6 fixed the bug.

[99p]

looks perfect!
thanks kitao! ;D