所有我想做的是创建一个真正简单的平移和缩放功能在2D与OpenGL通过pyglet。正如你所看到的,缩放是完美的工作后,第一次跳转:(然后再一次,拖动(平移)也工作,但它也跳转(它跳转了一个相当大的)。
下面是我的简化代码和一个视频(pyglet_test.mp4),展示了它的行为:
import pyglet
from pyglet.gl import *
# Zooming constants
ZOOM_IN_FACTOR = 1.2
ZOOM_OUT_FACTOR = 1/ZOOM_IN_FACTOR
class App(pyglet.window.Window):
def __init__(self, width, height, *args,**kwargs):
# Create GL configuration
conf = Config( sample_buffers=1,
samples=4,
depth_size=16,
double_buffer=True )
# Initialize parent
super().__init__( width, height, config=conf, *args,**kwargs )
# Create Group
self.group = group = pyglet.graphics.Group()
# Create Batch
self.batch = batch = pyglet.graphics.Batch()
# Create QUAD for testing and add it to batch
batch.add(
4, GL_QUADS, group,
('v2i', ( -50, -50,
50, -50,
50, 50,
-50, 50 )),
('c3B', ( 255, 0, 0,
255, 255, 0,
0, 255, 0,
0, 0, 255 ))
)
# Initialize OpenGL
self.init_gl()
# Initialize camera values
self.camera_x = 0
self.camera_y = 0
self.camera_zoom = 1
def init_gl(self):
# Set clear color
glClearColor(0/255, 0/255, 0/255, 0/255)
# Set antialiasing
glEnable( GL_LINE_SMOOTH )
glEnable( GL_POLYGON_SMOOTH )
glHint( GL_LINE_SMOOTH_HINT, GL_NICEST )
# Set alpha blending
glEnable( GL_BLEND )
glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA )
# Set viewport
glViewport( 0, 0, self.width, self.height )
# Initialize Projection matrix
glMatrixMode( GL_PROJECTION )
glLoadIdentity()
# Set orthographic projection matrix
glOrtho( 0, self.width, 0, self.height, 1, -1 )
# Initialize Modelview matrix
glMatrixMode( GL_MODELVIEW )
glLoadIdentity()
# Save the default modelview matrix
glPushMatrix()
def on_resize(self, width, height):
# Initialize OpenGL for new dimensions
self.width = width
self.height = height
self.init_gl()
def camera_matrix(transformations):
# Create camera setter function
def set_camera(self):
# Take saved matrix off the stack and reset it
glMatrixMode( GL_MODELVIEW )
glPopMatrix()
glLoadIdentity()
# Call wrapped function
transformations(self)
# Save default matrix again with camera translation
glPushMatrix()
# Return wrapper function
return set_camera
@camera_matrix
def move_camera(self):
# Move to camera position
glTranslatef( self.camera_x, self.camera_y, 0 )
# Scale camera
glScalef( self.camera_zoom, self.camera_zoom, 1 )
@camera_matrix
def zoom_camera(self):
# Move to camera position
glTranslatef( self.camera_x, self.camera_y, 0 )
# Scale camera
glScalef( self.camera_zoom, self.camera_zoom, 1 )
# Move back from camera position
glTranslatef( -self.camera_x, -self.camera_y, 0 )
def on_mouse_drag(self, x, y, dx, dy, button, modifiers):
# Move camera
self.camera_x += dx
self.camera_y += dy
self.move_camera()
def on_mouse_scroll(self, x, y, dx, dy):
# Get scale factor
f = ZOOM_IN_FACTOR if dy < 0 else ZOOM_OUT_FACTOR if dy > 0 else 1
# If zoom_level is in the proper range
if .2 < self.camera_zoom*f < 5:
# Zoom camera
self.camera_x = x
self.camera_y = y
self.camera_zoom *= f
self.zoom_camera()
def on_draw(self):
# Clear window with ClearColor
glClear( GL_COLOR_BUFFER_BIT )
# Pop default matrix onto current matrix
glMatrixMode( GL_MODELVIEW )
glPopMatrix()
# Save default matrix again
glPushMatrix()
# Move to center of the screen
glTranslatef( self.width/2, self.height/2, 0 )
# Draw objects
self.batch.draw()
def run(self):
pyglet.app.run()
# Create instance of app and run it
App(500, 500).run()
2条答案
按热度按时间9bfwbjaz1#
又是一天的煎熬之后,我终于找到了解决的办法:在2D中,执行基于鼠标坐标(枢轴点)的缩放和右键单击并拖动平移而不跳转的最简单方法是使用
glOrtho()
函数更改投影矩阵。这是我的原始代码的简化版本--如果您使用的是Pyglet,数据量很大,您应该考虑使用Groups和Batches,但是为了更容易理解,我在这里使用了
glBegin()
、glColor()
、glVertex()
、glEnd()
函数来绘制。bf1o4zei2#
像
glTranslatef
这样的函数并不是绝对有效的,相反,它们会将“世界”移动指定的量,所以如果你说glTranslatef(100,100)
,你最终会从你现在所在的位置向右和向下移动100个单位,而不是100, 100
。它们在后台所做的就是修改当前的视图矩阵。要实现这一点,需要编写如下代码: