Planet-Miner/godot/PlanetMeshFace.gd

78 lines
2.5 KiB
GDScript

@tool
extends MeshInstance3D
class_name PlantetMeshFace
@export var normal : Vector3
func regenerate_mesh(planet_data):
var arrays := []
arrays.resize(Mesh.ARRAY_MAX)
var vertex_array := PackedVector3Array()
var uv_array := PackedVector2Array()
var normal_array := PackedVector3Array()
var index_array := PackedInt32Array()
var resolution : int = planet_data.resolution
var num_vertices : int = resolution * resolution
var num_indices : int = (resolution-1) * (resolution-1) * 6
vertex_array.resize(num_vertices)
normal_array.resize(num_vertices)
uv_array.resize(num_vertices)
index_array.resize(num_indices)
var tri_index : int = 0
var a_axis := Vector3(normal.y, normal.z, normal.x)
var b_axis : Vector3 = normal.cross(a_axis)
for y in range(resolution):
for x in range(resolution):
var i : int = x + y*resolution
var percent := Vector2(x,y) / (resolution-1)
var point_on_cube : Vector3 = normal + (percent.x - 0.5)*2.0*a_axis + (percent.y - 0.5)*2.0*b_axis
var point_on_sphere = point_on_cube.normalized()
var point_on_planet = planet_data.point_on_planet(point_on_sphere)
vertex_array[i] = point_on_planet
if x != resolution-1 and y != resolution-1:
index_array[tri_index + 2] = i
index_array[tri_index + 1] = i+resolution+1
index_array[tri_index] = i+resolution
index_array[tri_index + 5] = i
index_array[tri_index + 4] = i+1
index_array[tri_index + 3] = i+resolution+1
tri_index += 6
for a in range(0, index_array.size(), 3):
var b : int = a + 1
var c : int = a + 2
var ab : Vector3 = vertex_array[index_array[b]] - vertex_array[index_array[a]]
var bc : Vector3 = vertex_array[index_array[c]] - vertex_array[index_array[b]]
var ca : Vector3 = vertex_array[index_array[a]] - vertex_array[index_array[c]]
var cross_ab_bc : Vector3 = bc.cross(ab)
var cross_bc_ca : Vector3 = ca.cross(bc)
var cross_ca_ab : Vector3 = ab.cross(ca)
normal_array[index_array[a]] += cross_ab_bc + cross_bc_ca + cross_ca_ab
normal_array[index_array[b]] += cross_ab_bc + cross_bc_ca + cross_ca_ab
normal_array[index_array[c]] += cross_ab_bc + cross_bc_ca + cross_ca_ab
for i in range(normal_array.size()):
normal_array[i] = normal_array[i].normalized()
arrays[Mesh.ARRAY_VERTEX] = vertex_array
arrays[Mesh.ARRAY_NORMAL] = normal_array
arrays[Mesh.ARRAY_TEX_UV] = uv_array
arrays[Mesh.ARRAY_INDEX] = index_array
call_deferred("_update_mesh", arrays)
func _update_mesh(arrays : Array):
var _mesh := ArrayMesh.new()
_mesh.add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, arrays)
self.mesh = _mesh