Added a very simple light source so the 3D models now have simple shading applied to them.

engine.py

@@ -1,5 +1,6 @@
 from vectors import Vector2d, Vector3d, Vector4d
 from matrix import Matrix3x3
+from triangle import Triangle
 
 class Engine:
 	def __init__(self, width, height):
@@ -41,6 +42,4 @@ class Mesh:
 				row1 = self.vertices[int(tmp[2]) - 1]
 				row2 = self.vertices[int(tmp[3]) - 1]
 
-				tri = Matrix3x3(row0, row1, row2)
+				self.triangles.append(Triangle(Matrix3x3(row0, row1, row2)))
-
-				self.triangles.append(tri)#Vector3d(x - 1, y - 1, z - 1))				

main.py

@@ -4,16 +4,31 @@ import copy
 from matrix import Matrix4x4, Matrix3x3
 from vectors import Vector4d, Vector3d, Vector2d
 from engine import Mesh
+from triangle import Triangle
 
 ui = window.Window(600, 600)
 near_plane = 0.1
 far_plane = 1000.0
 fov = 90.0
 
-tris = Mesh()
+tris =[
+Matrix3x3(Vector3d(0.0,0.0,0.0),Vector3d(0.0,1.0,0.0),Vector3d(1.0,1.0,0.0)),
+Matrix3x3(Vector3d(0.0,0.0,0.0),Vector3d(1.0,1.0,0.0),Vector3d(1.0,0.0,0.0)),
+Matrix3x3(Vector3d(1.0,0.0,0.0),Vector3d(1.0,1.0,0.0),Vector3d(1.0,1.0,1.0)),
+Matrix3x3(Vector3d(1.0,0.0,0.0),Vector3d(1.0,1.0,1.0),Vector3d(1.0,0.0,1.0)),
+Matrix3x3(Vector3d(1.0,0.0,1.0),Vector3d(1.0,1.0,1.0),Vector3d(0.0,1.0,1.0)),
+Matrix3x3(Vector3d(1.0,0.0,1.0),Vector3d(0.0,1.0,1.0),Vector3d(0.0,0.0,1.0)),
+Matrix3x3(Vector3d(0.0,0.0,1.0),Vector3d(0.0,1.0,1.0),Vector3d(0.0,1.0,0.0)),
+Matrix3x3(Vector3d(0.0,0.0,1.0),Vector3d(0.0,1.0,0.0),Vector3d(0.0,0.0,0.0)),
+Matrix3x3(Vector3d(0.0,1.0,0.0),Vector3d(0.0,1.0,1.0),Vector3d(1.0,1.0,1.0)),
+Matrix3x3(Vector3d(0.0,1.0,0.0),Vector3d(1.0,1.0,1.0),Vector3d(1.0,1.0,0.0)),
+Matrix3x3(Vector3d(1.0,0.0,1.0),Vector3d(0.0,0.0,1.0),Vector3d(0.0,0.0,0.0)),
+Matrix3x3(Vector3d(1.0,0.0,1.0),Vector3d(0.0,0.0,0.0),Vector3d(1.0,0.0,0.0))
+]
 
+#tris = Mesh()
 def main():
-	tris.load_obj_file('shuttle.obj')
+	#tris.load_obj_file('shuttle.obj')
 	
 	ui.thetax = 1
 	ui.window.bind('<Left>', left)
@@ -31,8 +46,7 @@ def right(event):
 	ui.theta += .01
 	
 def mouse_start(event):
-	#x, y = 
+	ui.canvas.old_coords = event.x, event.y
-	ui.canvas.old_coords = event.x, event.y #x, y
 	
 def mouse_end(event):
 	x, y = ui.canvas.old_coords[0] - event.x, ui.canvas.old_coords[1] - event.y
@@ -47,6 +61,8 @@ def mouse_end(event):
 		ui.thetax += .01
 	else:
 		ui.thetax -= .01
+		
+	draw_scene()
 	#ui.theta += x / ui.width
 	
 def draw_scene():
@@ -76,7 +92,9 @@ def draw_scene():
 	
 	rotation_matrix_x = Matrix4x4(row0, row1, row2, row3)
 	
-	for tri in tris.triangles:
+	triangles = []
+	
+	for tri in tris:
 		# Rotate on the z-axis
 		row0 = rotation_matrix_z.multiply_3d(tri.row0)
 		row1 = rotation_matrix_z.multiply_3d(tri.row1)
@@ -91,34 +109,76 @@ def draw_scene():
 		rotated_x = Matrix3x3(row0, row1, row2)
 		# The offset into the screen
 		translated = copy.copy(rotated_x)
-		translated.row0.z += 8.0
+		translated.row0.z += 3.0
-		translated.row1.z += 8.0
+		translated.row1.z += 3.0
-		translated.row2.z += 8.0
+		translated.row2.z += 3.0
-		# Scale into view
-		row0 = projection_matrix.multiply_3d(translated.row0)
-		row1 = projection_matrix.multiply_3d(translated.row1)
-		row2 = projection_matrix.multiply_3d(translated.row2)		
 		
-		projected = Matrix3x3(row0, row1, row2)
+		# Use cross-product to get the surface normal (a Vector3d)
+		x = translated.row1.x - translated.row0.x
+		y = translated.row1.y - translated.row0.y
+		z = translated.row1.z - translated.row0.z
+		line1 = Vector3d(x, y, z)
 		
-		projected.row0.x += 1
+		x = translated.row2.x - translated.row0.x
-		projected.row0.y += 1
+		y = translated.row2.y - translated.row0.y
-		projected.row1.x += 1
+		z = translated.row2.z - translated.row0.z
-		projected.row1.y += 1
+		line2 = Vector3d(x, y, z)
-		projected.row2.x += 1
-		projected.row2.y += 1
-		projected.row0.x *= .5 * ui.width
-		projected.row0.y *= .5 * ui.height
-		projected.row1.x *= .5 * ui.width
-		projected.row1.y *= .5 * ui.height
-		projected.row2.x *= .5 * ui.width		
-		projected.row2.y *= .5 * ui.height
 		
-		coords = [projected.row0.x, projected.row0.y, projected.row1.x, projected.row1.y, projected.row2.x, projected.row2.y]
+		normal = line1.cross_product(line2)
-		ui.canvas.create_polygon(coords, fill="", outline="black")
+		
+		# Now we normalize the normal
+		w = math.sqrt(normal.x * normal.x + normal.y * normal.y + normal.z * normal.z)
+		normal.x /= w
+		normal.y /= w
+		normal.z /= w
+		
+		# Do we display this triangle?
+		if normal.dot_product(translated.row0) < 0.0:
+			# Lighting
+			light = Vector3d(0, 0, -1) # Shining at the player.
+			
+			w = math.sqrt(light.x * light.x + light.y * light.y + light.z * light.z)
+			light.x /= w
+			light.y /= w
+			light.z /= w
+			
+			dot_product = normal.dot_product(light)
+			r = abs(int(255 * dot_product))
+			
+			# Scale into view
+			row0 = projection_matrix.multiply_3d(translated.row0)
+			row1 = projection_matrix.multiply_3d(translated.row1)
+			row2 = projection_matrix.multiply_3d(translated.row2)		
+			
+			projected = Matrix3x3(row0, row1, row2)
+			
+			projected.row0.x += 1
+			projected.row0.y += 1
+			projected.row1.x += 1
+			projected.row1.y += 1
+			projected.row2.x += 1
+			projected.row2.y += 1
+			projected.row0.x *= .5 * ui.width
+			projected.row0.y *= .5 * ui.height
+			projected.row1.x *= .5 * ui.width
+			projected.row1.y *= .5 * ui.height
+			projected.row2.x *= .5 * ui.width		
+			projected.row2.y *= .5 * ui.height
+			
+			t = Triangle(projected)
+			t.color = r
+			triangles.append(t)
+			
+	for projected in triangles:
+		r = projected.color
+		coords = [projected.coords.row0.x, projected.coords.row0.y, projected.coords.row1.x, projected.coords.row1.y, projected.coords.row2.x, projected.coords.row2.y]
+		ui.canvas.create_polygon(coords, fill=from_rgb(r, r, r), outline="black")
 		
 	ui.canvas.update()
 	
-	ui.canvas.after(100, draw_scene)
+	#ui.canvas.after(100, draw_scene)
+	
+def from_rgb(r, b, g):
+	return "#%02x%02x%02x" %(r, g, b)
 	
 main()

triangle.py

@@ -0,0 +1,7 @@
+import vectors
+
+class Triangle:
+	def __init__(self, coords):
+		self.coords = coords # Matrix3x3
+		self.object_id = None
+		self.color = None

vectors.py

@@ -17,7 +17,7 @@ class Vector3d:
 		# Returns the 'normal'.
 		x = self.y * vector3d.z - self.z * vector3d.y
 		y = self.z * vector3d.x - self.x * vector3d.z
-		z = self.x * vectored.y - self.y * vector3d.x
+		z = self.x * vector3d.y - self.y * vector3d.x
 		
 		return Vector3d(x, y, z)