Update render/core.py

render/core.py

@@ -8,7 +8,6 @@ from .canvas import Canvas
 from . import speedup
 
 
-# 2D part
 
 
 class Vec2d:
@@ -124,14 +123,13 @@ def draw_triangle(v1, v2, v3, canvas, color, wireframe=False):
         fill_top_flat_triangle(v2, v4, v3)
 
 
-# 3D part
 
 
 class Vec3d:
     __slots__ = "x", "y", "z", "arr"
 
     def __init__(self, *args):
-        # for Vec4d cast
+        
         if len(args) == 1 and isinstance(args[0], Vec4d):
             vec4 = args[0]
             arr_value = (vec4.x, vec4.y, vec4.z)
@@ -183,7 +181,7 @@ class Vec4d(Mat4d):
         self.arr = self.value.reshape((1, 4))
 
 
-# Math util
+
 def normalize(v: Vec3d):
     return Vec3d(*speedup.normalize(*v.arr))
 
@@ -210,16 +208,7 @@ def get_light_intensity(face) -> float:
 
 
 def look_at(eye: Vec3d, target: Vec3d, up: Vec3d = Vec3d(0, -1, 0)) -> Mat4d:
-    """
-    http://www.songho.ca/opengl/gl_camera.html#lookat
-
-    Args:
-        eye: 摄像机的世界坐标位置
-        target: 观察点的位置
-        up: 就是你想让摄像机立在哪个方向
-            https://stackoverflow.com/questions/10635947/what-exactly-is-the-up-vector-in-opengls-lookat-function
-            这里默认使用了 0, -1, 0， 因为 blender 导出来的模型数据似乎有问题，导致y轴总是反的，于是把摄像机的up也翻一下得了。
-    """
+    
     f = normalize(eye - target)
     l = normalize(cross_product(up, f))  # noqa: E741
     u = cross_product(f, l)
@@ -235,35 +224,7 @@ def look_at(eye: Vec3d, target: Vec3d, up: Vec3d = Vec3d(0, -1, 0)) -> Mat4d:
 
 
 def perspective_project(r, t, n, f, b=None, l=None):  # noqa: E741
-    """
-    目的：
-        把相机坐标转换成投影在视网膜的范围在(-1, 1)的笛卡尔坐标
-
-    原理：
-        对于x，y坐标，相似三角形可以算出投影点的x，y
-        对于z坐标，是假设了near是-1，far是1，然后带进去算的
-        http://www.songho.ca/opengl/gl_projectionmatrix.html
-        https://www.scratchapixel.com/lessons/3d-basic-rendering/perspective-and-orthographic-projection-matrix/opengl-perspective-projection-matrix
-
-    推导出来的矩阵：
-        [
-            2n/(r-l) 0        (r+l/r-l)   0
-            0        2n/(t-b) (t+b)/(t-b) 0
-            0        0        -(f+n)/f-n  (-2*f*n)/(f-n)
-            0        0        -1          0
-        ]
-
-    实际上由于我们用的视网膜(near pane)是个关于远点对称的矩形，所以矩阵简化为：
-        [
-            n/r      0        0           0
-            0        n/t      0           0
-            0        0        -(f+n)/f-n  (-2*f*n)/(f-n)
-            0        0        -1          0
-        ]
-
-    Args:
-        r: right, t: top, n: near, f: far, b: bottom, l: left
-    """
+    
     return Mat4d(
         [
             [n / r, 0, 0, 0],
@@ -291,8 +252,7 @@ def draw(screen_vertices, world_vertices, model, canvas, wireframe=True):
 
 
 def draw_with_z_buffer(screen_vertices, world_vertices, model, canvas):
-    """ z-buffer algorithm
-    """
+
     intensities = []
     triangles = []
     for i, triangle_indices in enumerate(model.indices):
@@ -319,13 +279,7 @@ def draw_with_z_buffer(screen_vertices, world_vertices, model, canvas):
 
 
 def render(model, height, width, filename, cam_loc, wireframe=False):
-    """
-    Args:
-        model: the Model object
-        height: cavas height
-        width: cavas width
-        picname: picture file name
-    """
+
     model_matrix = Mat4d([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]])
     # TODO: camera configration
     view_matrix = look_at(Vec3d(cam_loc[0], cam_loc[1], cam_loc[2]), Vec3d(0, 0, 0))
@@ -339,9 +293,7 @@ def render(model, height, width, filename, cam_loc, wireframe=False):
         return projection_matrix * view_matrix * world_vertex
 
     def ndc(v):
-        """
-        各个坐标同时除以 w，得到 NDC 坐标
-        """
+
         v = v.value
         w = v[3, 0]
         x, y, z = v[0, 0] / w, v[1, 0] / w, v[2, 0] / w
@@ -357,7 +309,7 @@ def render(model, height, width, filename, cam_loc, wireframe=False):
             0.5 * (f - n) * v.value[2, 0] + 0.5 * (f + n),
         )
 
-    # the render pipeline
+
     screen_vertices = [viewport(ndc(mvp(v))) for v in model.vertices]
 
     with Canvas(filename, height, width) as canvas: