我一直在尝试旋转对象,但是旋转时,我意识到它只是平坦的。奇怪的是,我可以清楚地看到z dim的输入在那儿,只是没有考虑到。这是我的代码:
import moderngl
from PyQt5 import QtOpenGL, QtCore, QtGui
from PyQt5.QtCore import Qt, pyqtSignal
import numpy as np
from pyrr import matrix44
cube_verts4 = np.array([
-1.0, 1.0, -1.0, 1.0,
-1.0, -1.0, -1.0, 1.0,
1.0, -1.0, -1.0, 1.0,
1.0, 1.0, -1.0, 1.0,
-1.0, 1.0, 1.0, 1.0,
-1.0, -1.0, 1.0, 1.0,
1.0, -1.0, 1.0, 1.0,
1.0, 1.0, 1.0, 1.0,
], dtype=np.float32)
cube_ibo_idxs = np.array([
0, 1, 2,
2, 3, 1,
3, 2, 6,
6, 5, 3,
5, 6, 7,
7, 4, 5,
4, 7, 1,
1, 0, 4,
0, 3, 5,
5, 4, 0,
1, 7, 6,
6, 2, 1
], dtype=np.int32)
class OpenGLWindowWidget(QtOpenGL.QGLWidget):
vsync = True
remove_event = pyqtSignal(str)
def __init__(self, **kwargs):
super().__init__(**kwargs)
self.gl_version = (4, 3)
fmt = QtOpenGL.QGLFormat()
# need compute shader stuff
fmt.setVersion(self.gl_version[0], self.gl_version[1])
fmt.setProfile(QtOpenGL.QGLFormat.CoreProfile)
fmt.setDepthBufferSize(24)
fmt.setDoubleBuffer(True)
fmt.setSwapInterval(1 if self.vsync else 0)
self.ctx = None
self.timer = QtCore.QTimer(self)
self.timer.timeout.connect(self.update)
self.timer.start(16)
self.last_mouse_pos = None
self.rotation_x = 0
self.rotation_y = 0
def mousePressEvent(self, event: QtGui.QMouseEvent) -> None:
self.last_mouse_pos = event.pos()
def mouseMoveEvent(self, event: QtGui.QMouseEvent) -> None:
dx = event.x() - self.last_mouse_pos.x()
dy = event.y() - self.last_mouse_pos.y()
if event.buttons() & Qt.LeftButton:
self.rotation_x += dx * 0.01
self.rotation_y += dy * 0.01
self.last_mouse_pos = event.pos()
@property
def gl_version_code(self) -> int:
return self.gl_version[0] * 100 + self.gl_version[1] * 10
@property
def aspect_ratio(self):
return self.width() / self.height()
def initializeGL(self) -> None:
self.ctx = moderngl.create_context(
require=self.gl_version_code)
self.prog = self.ctx.program(
vertex_shader='''
#version 330
in vec4 vertex;
in float power;
uniform mat4 mvp_matrix;
void main() {
gl_Position = vec4(mvp_matrix * vertex);
}
''',
fragment_shader='''
#version 330
out vec4 color;
void main() {
color = vec4(0.0, 0.0, 0.0, 1.0);
}
''',
)
self.mvp_matrix = self.prog["mvp_matrix"]
self.vbo = self.ctx.buffer(
cube_verts4.astype('f4').tobytes())
self.ibo = self.ctx.buffer(
cube_ibo_idxs.astype('i4').tobytes())
vao_content = [
# 4 floats are assigned to the 'in' variable named 'vertex' in the shader code
(self.vbo, '4f', 'vertex'),
]
self.vao = self.ctx.vertex_array(self.prog, vao_content,
self.ibo)
def paintGL(self):
target_width = 2
target_height = 2
r_aspect_ratio = target_width / target_height
if self.aspect_ratio > r_aspect_ratio:
v_a = self.aspect_ratio / r_aspect_ratio
projection = matrix44.create_orthogonal_projection_matrix(
-v_a * target_width / 2.0,
v_a * target_width / 2.0, -target_height / 2.0,
target_height / 2.0, 0, 100, dtype=np.float32)
else:
a_v = r_aspect_ratio / self.aspect_ratio
projection = matrix44.create_orthogonal_projection_matrix(
-target_width / 2.0, target_width / 2.0,
-a_v * target_height / 2.0,
a_v * target_height / 2.0,
0, 100, dtype=np.float32)
rotate = matrix44.create_from_y_rotation(
self.rotation_x) * matrix44.create_from_x_rotation(
self.rotation_y)
self.mvp_matrix.write((rotate * projection).astype('f4').tobytes())
self.ctx.viewport = (0, 0, self.width(), self.height())
self.ctx.clear(0.0, 1.0, 1.0)
self.vao.render()
self.ctx.finish()
这就是我旋转时得到的结果。
我本来期望立方体的轮廓,而不是平面的轮廓。
我什至不知道是什么原因造成了这种影响。最初,我认为这与vec3的对齐方式有关,但是我替换了我的vertex + vbo代码,改为使用vec4s,但仍然无法正常工作。我不知道如何“去除”我的深度。我不熟悉
pyrr
,所以也许有些矩阵变换是不正确的? 最佳答案
元素索引不构成多维数据集。使用以下索引:
cube_ibo_idxs = np.array([
0, 1, 2, 0, 2, 3,
3, 2, 6, 3, 6, 7,
7, 6, 5, 7, 5, 4,
7, 4, 0, 7, 0, 3,
4, 5, 1, 4, 1, 0,
1, 5, 6, 1, 6, 2
], dtype=np.int32)
pyrr Matrix44操作返回
numpy.array
。对于数组,
*
表示逐元素乘法,而@
表示矩阵乘法。请参见array
。因此,您不想使用@
的*
istead。或者,您可以使用numpy.matmul
。在正投影中,近平面设置为0,远平面设置为100。
projection = matrix44.create_orthogonal_projection_matrix(
v_a * -target_width / 2.0, v_a * target_width / 2.0,
-target_height / 2.0, target_height / 2.0,
0, 100, dtype=np.float32)
由于几何的中心在(0,0,0),因此立方体网格被长方体视图体积的近平面部分裁剪。更改近平面(例如-100)或在近平面和远平面之间绘制立方体。这意味着您必须沿z轴平移网格。由于(视图空间)z轴指向视口(在Right-handed系统中),因此您必须沿负z方向平移网格(例如
-3
):rotate = matrix44.create_from_y_rotation(-self.rotation_x) @ \
matrix44.create_from_x_rotation(-self.rotation_y) @ \
matrix44.create_from_translation(np.array([0, 0, -3], dtype=np.float32))
此外,我建议启用Depth Test。参见ModernGL - Context:
self.ctx.enable(moderngl.DEPTH_TEST)
使用以下功能绘制几何:
def paintGL(self):
target_width = 4
target_height = 4
r_aspect_ratio = target_width / target_height
if self.aspect_ratio > r_aspect_ratio:
v_a = self.aspect_ratio / r_aspect_ratio
projection = matrix44.create_orthogonal_projection_matrix(
v_a * -target_width / 2.0, v_a * target_width / 2.0,
-target_height / 2.0, target_height / 2.0,
0, 100, dtype=np.float32)
else:
a_v = r_aspect_ratio / self.aspect_ratio
projection = matrix44.create_orthogonal_projection_matrix(
-target_width / 2.0, target_width / 2.0,
-a_v * target_height / 2.0, a_v * target_height / 2.0,
0, 100, dtype=np.float32)
rotate = matrix44.create_from_y_rotation(-self.rotation_x) @ \
matrix44.create_from_x_rotation(-self.rotation_y) @ \
matrix44.create_from_translation(np.array([0, 0, -3], dtype=np.float32))
self.mvp_matrix.write((rotate @ projection).astype('f4').tobytes())
self.ctx.viewport = (0, 0, self.width(), self.height())
self.ctx.clear(0.0, 1.0, 1.0)
self.ctx.enable(moderngl.DEPTH_TEST)
self.vao.render()
self.ctx.finish()
如果使用以下顶点着色器
#version 330
in vec4 vertex;
in float power;
out vec4 v_clip_pos;
uniform mat4 mvp_matrix;
void main() {
v_clip_pos = mvp_matrix * vertex;
gl_Position = v_clip_pos;
}
和片段着色器
#version 330
in vec4 v_clip_pos;
out vec4 color;
void main() {
vec3 ndc_pos = v_clip_pos.xyz / v_clip_pos.w;
vec3 dx = dFdx( ndc_pos );
vec3 dy = dFdy( ndc_pos );
vec3 N = normalize(cross(dx, dy));
N *= sign(N.z);
vec3 L = vec3(0.0, 0.0, 1.0);
float NdotL = dot(N, L);
vec3 diffuse_color = vec3(0.5) * NdotL;
color = vec4( diffuse_color.rgb, 1.0 );
}
那么您可以实现轻微的3D效果。