I've been looking around for a way to anti-alias lines in OpenGL, but none of them seem to work... here's some example code:
import pyglet
from pyglet.gl import *
window = pyglet.window.Window(resizable=True)
@window.event
def on_draw():
window.clear()
pyglet.gl.glColor4f(1.0,0,0,1.0)
glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
glEnable (GL_BLEND)
glEnable (GL_LINE_SMOOTH);
glHint (GL_LINE_SMOOTH_HINT, GL_DONT_CARE)
开发者_StackOverflow glLineWidth (3)
pyglet.graphics.draw(2, pyglet.gl.GL_LINES,
('v2i', (10, 15, 300, 305))
)
pyglet.app.run()
Can anyone see what I am doing wrong?
Allow Pyglet to use an extra sample buffer might help. Change your window line to this:
config = pyglet.gl.Config(sample_buffers=1, samples=4)
window = pyglet.window.Window(config=config, resizable=True)
This works for me.
It's a bit hard to say for sure. The first thing is probably to change your hint from GL_DONT_CARE to GL_NICEST. It probably won't make much difference with most graphics cards, but it might help a little.
Other than that, it's a bit hard to say. Here's a bit of code (in C++; sorry):
void draw_line(float y_offset) {
glBegin(GL_LINES);
glColor3f(1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, 0.0f+y_offset, -1.0f);
glVertex3f(1.0f, 0.1f+y_offset, -1.0f);
glEnd();
}
void draw() {
glClearColor(0.0f, 0.0f, 0.2f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glFrustum(-1.2f, 1.2f, -0.2f, 0.2f, 0.8f, 5.0f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glEnable(GL_DEPTH_TEST);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glLineWidth(3.0f);
glDisable(GL_LINE_SMOOTH);
draw_line(0.0f);
glEnable(GL_LINE_SMOOTH);
glHint(GL_LINE_SMOOTH_HINT, GL_DONT_CARE);
draw_line(-0.1f);
glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
draw_line(-0.2f);
glFlush();
}
And here's what I'm getting as output from that:
The difference when line-smoothing is turned on seems pretty obvious. The difference between GL_DONT_CARE and GL_NICEST is (at most) a lot less so.
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