Distinguishing between a mouse down and a mouse hold

Im currently working on a little graphics library for pyglet. The module is used to开发者_如何学运维 make vector graphics composed entirely of lines.

In its develoment i have have run into a problem where, clicking to drag (and move a point) also causes fires an on_mouse_press event that creates a new link between the last active link and the point you are trying to drag.

I cant seem to think of any way to fix this that dosent make creating links between points feel laggy, i have creating links on_mouse_release instead so that i could determine if the mouse had been draged before linking the point.

Does anyone else have any bright ideas on how i can get this to work without appearing laggy.

EDIT: to clarify im using pyglet with python

---

#!/usr/bin/python
import pyglet
from time import time, sleep

class Window(pyglet.window.Window):
    def __init__(self, refreshrate):
        super(Window, self).__init__(vsync = False)
        self.frames = 0
        self.framerate = pyglet.text.Label(text='Unknown', font_name='Verdana', font_size=8, x=10, y=10, color=(255,255,255,255))
        self.last = time()
        self.alive = 1
        self.refreshrate = refreshrate
        self.click = None
        self.drag = False

    def on_draw(self):
        self.render()

    def on_mouse_press(self, x, y, button, modifiers):
        self.click = x,y

    def on_mouse_drag(self, x, y, dx, dy, buttons, modifiers):
        if self.click:
            self.drag = True
            print 'Drag offset:',(dx,dy)

    def on_mouse_release(self, x, y, button, modifiers):
        if not self.drag and self.click:
            print 'You clicked here', self.click, 'Relese point:',(x,y)
        else:
            print 'You draged from', self.click, 'to:',(x,y)
        self.click = None
        self.drag = False

    def render(self):
        self.clear()
        if time() - self.last >= 1:
            self.framerate.text = str(self.frames)
            self.frames = 0
            self.last = time()
        else:
            self.frames += 1
        self.framerate.draw()
        self.flip()

    def on_close(self):
        self.alive = 0

    def run(self):
        while self.alive:
            self.render()
            # ----> Note: <----
            #  Without self.dispatc_events() the screen will freeze
            #  due to the fact that i don't call pyglet.app.run(),
            #  because i like to have the control when and what locks
            #  the application, since pyglet.app.run() is a locking call.
            event = self.dispatch_events()
            sleep(1.0/self.refreshrate)

win = Window(23) # set the fps
win.run()

Short description:

• Keep track of the current mouse state within the window
• Keep track of startpoint of mouse event
• At mouse release, do waht you want to do or update whatever it is within the drag.

I know it's an old question, but it's under the "unanswered" so hoping to get it resolved and out of the list.

---

On MouseDown set a boolean variable to indicate that other events should be ignored.

private bool IgnoreEvents { set; get; }

...

protected void Control_MouseDown(object sender, EventArgs e)
{
    //Dragging or holding.
    this.IgnoreEvents = true;
}

protected void Control_MouseUp(object sender, EventArgs e)
{
    //Finished dragging or holding.
    this.IgnoreEvents = false;
}

protected void OtherControl_SomeOtherEvent(object sender, EventArgs e)
{
    if (this.IgnoreEvents)
        return;

    //Otherwise to normal stuff here.
}

You'll need to tweak this to work with your code of course but it should be a good start.