Using TheOneLoneCoder's 'Code-It-Yourself! 3D Graphics Engine Part #1' video as a reference, I ported some of his code to create the first step in this engine, perspective.

2020-07-13 14:04:41 -05:00
parent 6f25f9e0d8
commit 5f83619244
2 changed files with 129 additions and 2 deletions
@@ -1,8 +1,133 @@
 import window
+import math
+import copy
+
+ui = window.Window(600, 600)
+near_plane = 0.1
+far_plane = 1000.0
+fov = 90.0
+
+tris = [
+	# SOUTH
+	[ [0.0, 0.0, 0.0],    [0.0, 1.0, 0.0],    [1.0, 1.0, 0.0] ],
+	[ [0.0, 0.0, 0.0],    [1.0, 1.0, 0.0],    [1.0, 0.0, 0.0 ]],
+
+	# EAST                                                      
+	[ [1.0, 0.0, 0.0],    [1.0, 1.0, 0.0],    [1.0, 1.0, 1.0 ]],
+	[ [1.0, 0.0, 0.0],    [1.0, 1.0, 1.0],    [1.0, 0.0, 1.0 ]],
+
+	# NORTH                                                     
+	[ [1.0, 0.0, 1.0],    [1.0, 1.0, 1.0],    [0.0, 1.0, 1.0 ]],
+	[ [1.0, 0.0, 1.0],    [0.0, 1.0, 1.0],    [0.0, 0.0, 1.0 ]],
+
+	# WEST                                                      
+	[[ 0.0, 0.0, 1.0],    [0.0, 1.0, 1.0],    [0.0, 1.0, 0.0 ]],
+	[ [0.0, 0.0, 1.0],    [0.0, 1.0, 0.0],    [0.0, 0.0, 0.0 ]],
+
+	# TOP                                                       
+	[[ 0.0, 1.0, 0.0],    [0.0, 1.0, 1.0],    [1.0, 1.0, 1.0 ]],
+	[[ 0.0, 1.0, 0.0],    [1.0, 1.0, 1.0],    [1.0, 1.0, 0.0 ]],
+
+	# BOTTOM                                                    
+	[[ 1.0, 0.0, 1.0],    [0.0, 0.0, 1.0],    [0.0, 0.0, 0.0 ]],
+	[[ 1.0, 0.0, 1.0],    [0.0, 0.0, 0.0],    [1.0, 0.0, 0.0 ]]
+]
+
+def matric_mul(d_vector, transform_mat):
+	out_matrix = []
+	out_matrix.append(d_vector[0] * transform_mat[0][0] + d_vector[1] * transform_mat[1][0] + d_vector[2] * transform_mat[2][0] + transform_mat[3][0]) # x
+	out_matrix.append(d_vector[0] * transform_mat[0][1] + d_vector[1] * transform_mat[1][1] + d_vector[2] * transform_mat[2][1] + transform_mat[3][1]) # y
+	out_matrix.append(d_vector[0] * transform_mat[0][2] + d_vector[1] * transform_mat[1][2] + d_vector[2] * transform_mat[2][2] + transform_mat[3][2]) # z
+	# 4th row
+	w = d_vector[0] * transform_mat[0][3] + d_vector[1] * transform_mat[1][3] + d_vector[2] * transform_mat[2][3] + transform_mat[3][3]
+	
+	if w != 0:
+		out_matrix[0] /= w
+		out_matrix[1] /= w
+		out_matrix[2] /= w
+		
+	return out_matrix
+	
+def make_matrix(row1, row2, row3, row4):
+	mat = []
+	mat.append([])
+	mat[0].append([row1[0], row1[1], row1[2], row1[3]])
+	mat.append([])
+	mat[1].append([row2[0], row2[1], row2[2], row2[3]])
+	mat.append([])
+	mat[2].append([row3[0], row3[1], row3[2], row3[3]])
+	mat.append([])
+	mat[3].append([row4[0], row4[1], row4[2], row4[3]])
+	
+	return mat

 def main():
-	ui = window.Window(600, 600)
-	
+	ui.window.after(0, draw_scene)
 	ui.show()
+
+	
+def draw_scene():
+	ui.canvas.delete("all")
+	ui.theta += .01
+	projection_matrix = []
+	rotation_matrix_z = []
+	rotation_matrix_x = []
+	aspect_ratio = ui.height / ui.width
+	fov_rad = ui.theta / math.tan(fov * 0.5 / 180.0 * math.pi)
+
+	projection_matrix.append([aspect_ratio * fov_rad, 0, 0, 0])
+	projection_matrix.append([0, fov_rad, 0, 0])
+	projection_matrix.append([0, 0, far_plane / (far_plane - near_plane), 1.0])
+	projection_matrix.append([0, 0, -far_plane * near_plane / (far_plane - near_plane), 0])
+	
+	rotation_matrix_z.append([math.cos(ui.theta), math.sin(ui.theta), 0, 0])
+	rotation_matrix_z.append([-math.sin(ui.theta), math.cos(ui.theta), 0, 0])
+	rotation_matrix_z.append([0, 0, 1, 0])
+	rotation_matrix_z.append([0, 0, 0, 1])
+	#--------------------------------------------
+	rotation_matrix_x.append([1, 0, 0, 0])
+	rotation_matrix_x.append([0, math.cos(ui.theta * 0.5), math.sin(ui.theta * 0.5), 0])
+	rotation_matrix_x.append([0, -math.sin(ui.theta * 0.5), math.cos(ui.theta * 0.5), 0])
+	rotation_matrix_x.append([0, 0, 0, 1])
+
+	for tri in tris:
+		rotated_z = []
+		rotated_z.append(matric_mul(tri[0], rotation_matrix_z))
+		rotated_z.append(matric_mul(tri[1], rotation_matrix_z))
+		rotated_z.append(matric_mul(tri[2], rotation_matrix_z))
+		
+		rotated_x = []
+		rotated_x.append(matric_mul(rotated_z[0], rotation_matrix_x))
+		rotated_x.append(matric_mul(rotated_z[1], rotation_matrix_x))
+		rotated_x.append(matric_mul(rotated_z[2], rotation_matrix_x))
+		
+		translated = copy.copy(rotated_x)
+		translated[0][2] = rotated_x[0][2] + 3.0
+		translated[1][2] = rotated_x[1][2] + 3.0
+		translated[2][2] = rotated_x[2][2] + 3.0
+		
+		projected = []
+		projected.append(matric_mul(translated[0], projection_matrix))
+		projected.append(matric_mul(translated[1], projection_matrix))
+		projected.append(matric_mul(translated[2], projection_matrix))
+		
+		projected[0][0] += 1
+		projected[0][1] += 1
+		projected[1][0] += 1
+		projected[1][1] += 1
+		projected[2][0] += 1
+		projected[2][1] += 1
+		projected[0][0] *= .5 * ui.width
+		projected[0][1] *= .5 * ui.height
+		projected[1][0] *= .5 * ui.width
+		projected[1][1] *= .5 * ui.height
+		projected[2][0] *= .5 * ui.width		
+		projected[2][1] *= .5 * ui.height
+		coords = [projected[0][0], projected[0][1], projected[1][0], projected[1][1], projected[2][0], projected[2][1]]
+		ui.canvas.create_polygon(coords, fill="", outline="black")
+		
+	ui.canvas.update()
+	
+	ui.canvas.after(100, draw_scene)
 	
 main()
@@ -8,6 +8,8 @@ class Window:
 		self.canvas.pack()
 		self.width = width		
 		self.height = height
+		self.theta = 1
+		self.triangles = []
 		
 	def show(self):
 		self.window.mainloop()