/
physics_impulse.py
88 lines (59 loc) · 2.73 KB
/
physics_impulse.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
# Physics Impulse
import harfang as hg
hg.InputInit()
hg.WindowSystemInit()
res_x, res_y = 1280, 720
win = hg.RenderInit('Harfang - Physics Force/Impulse (Press space to alternate)', res_x, res_y, hg.RF_VSync | hg.RF_MSAA4X)
pipeline = hg.CreateForwardPipeline()
res = hg.PipelineResources()
# create models
vtx_layout = hg.VertexLayoutPosFloatNormUInt8()
cube_mdl = hg.CreateCubeModel(vtx_layout, 1, 1, 1)
cube_ref = res.AddModel('cube', cube_mdl)
ground_mdl = hg.CreateCubeModel(vtx_layout, 50, 0.01, 50)
ground_ref = res.AddModel('ground', ground_mdl)
# create material
prg_ref = hg.LoadPipelineProgramRefFromFile('resources_compiled/core/shader/default.hps', res, hg.GetForwardPipelineInfo())
mat = hg.CreateMaterial(prg_ref, 'uDiffuseColor', hg.Vec4(1, 1, 1), 'uSpecularColor', hg.Vec4(1, 1, 1))
# setup scene
scene = hg.Scene()
cam = hg.CreateCamera(scene, hg.TransformationMat4(hg.Vec3(0, 1.5, -5), hg.Vec3(hg.Deg(10), 0, 0)), 0.01, 1000)
scene.SetCurrentCamera(cam)
lgt = hg.CreateLinearLight(scene, hg.TransformationMat4(hg.Vec3(0, 0, 0), hg.Vec3(hg.Deg(30), hg.Deg(59), 0)), hg.Color(1, 1, 1), hg.Color(1, 1, 1), 10, hg.LST_Map, 0.002, hg.Vec4(2, 4, 10, 16))
cube_node = hg.CreatePhysicCube(scene, hg.Vec3(1, 1, 1), hg.TranslationMat4(hg.Vec3(0, 1.5, 0)), cube_ref, [mat], 2)
ground_node = hg.CreatePhysicCube(scene, hg.Vec3(100, 0.02, 100), hg.TranslationMat4(hg.Vec3(0, -0.005, 0)), ground_ref, [mat], 0)
clocks = hg.SceneClocks()
# scene physics
physics = hg.SceneBullet3Physics()
physics.SceneCreatePhysicsFromAssets(scene)
physics_step = hg.time_from_sec_f(1 / 60)
# main loop
keyboard = hg.Keyboard()
use_force = True
while not keyboard.Down(hg.K_Escape) and hg.IsWindowOpen(win):
keyboard.Update()
dt = hg.TickClock()
if keyboard.Pressed(hg.K_Space):
use_force = not use_force
world_pos = hg.GetT(cube_node.GetTransform().GetWorld())
dist_to_ground = world_pos.y - 0.5
if dist_to_ground < 1.0:
k = -(dist_to_ground - 1.0)
if use_force:
F = hg.Vec3(0, 1, 0) * k * 80 # apply a force inversely proportional to the distance to the ground
physics.NodeAddForce(cube_node, F, world_pos)
else:
stiffness = 10
cur_velocity = physics.NodeGetLinearVelocity(cube_node)
tgt_velocity = hg.Vec3(0, 1, 0) * k * stiffness # compute a velocity that brings us to 1 meter above the ground
I = tgt_velocity - cur_velocity # an impulse is an instantaneous change in velocity
physics.NodeAddImpulse(cube_node, I, world_pos)
physics.NodeWake(cube_node)
hg.SceneUpdateSystems(scene, clocks, dt, physics, physics_step, 3)
hg.SubmitSceneToPipeline(0, scene, hg.IntRect(0, 0, res_x, res_y), True, pipeline, res)
hg.Frame()
hg.UpdateWindow(win)
hg.RenderShutdown()
hg.DestroyWindow(win)
hg.WindowSystemShutdown()
hg.InputShutdown()