scene_capture_texture.py

# Toyota 2JZ-GTE Engine model by Serhii Denysenko (CGTrader: serhiidenysenko8256)
# URL : https://www.cgtrader.com/3d-models/vehicle/part/toyota-2jz-gte-engine-2932b715-2f42-4ecd-93ce-df9507c67ce8


import harfang as hg
import math

hg.InputInit()
hg.WindowSystemInit()

res_x, res_y, tex_size = 1024, 1024, 1024
win = hg.RenderInit('Scene Capture Texture - Press SpaceBar to capture', res_x, res_y, hg.RF_VSync | hg.RF_MSAA4X)


#Link precompiled assets folder to the project
hg.AddAssetsFolder("resources_compiled")

#Create Pipeline
pipeline = hg.CreateForwardPipeline()
res = hg.PipelineResources()

#Create a 1024*1024 frame buffer to draw the scene to
frame_buffer = hg.CreateFrameBuffer(tex_size, tex_size, hg.TF_RGBA8, hg.TF_D24, 4, 'framebuffer')
tex_color = hg.GetColorTexture(frame_buffer)

#Prepare screenshot requirements
tex_color_ref = res.AddTexture("tex_rb", tex_color)
tex_readback = hg.CreateTexture(tex_size, tex_size, "readback", hg.TF_ReadBack | hg.TF_BlitDestination, hg.TF_RGBA8)
picture = hg.Picture(tex_size, tex_size, hg.PF_RGBA32)

#Load scene
scene = hg.Scene()
ret = hg.LoadSceneFromAssets("car_engine/engine.scn", scene, res, hg.GetForwardPipelineInfo())

#Create the plane model
vtx_layout = hg.VertexLayoutPosFloatTexCoord0UInt8()
plane_mdl = hg.CreatePlaneModel(vtx_layout, 1, 1, 1, 1)
plane_ref = res.AddModel('plane', plane_mdl)

#Prepare the plane shader program
plane_prg = hg.LoadProgramFromAssets('shaders/texture')

#Main Loop 
frame = 0
state = "none"

while not hg.ReadKeyboard().Key(hg.K_Escape) and hg.IsWindowOpen(win):
    dt = hg.TickClock()

    #Update Scene and render to the frameBuffer
    scene.Update(dt)

    trs = scene.GetNode("engine_master").GetTransform()
    trs.SetRot(trs.GetRot() + hg.Vec3(0, hg.Deg(15) * hg.time_to_sec_f(dt), 0))

    view_id = 0
    view_id, pass_id = hg.SubmitSceneToPipeline(view_id, scene, hg.IntRect(0, 0, res_x, res_y), True, pipeline, res, frame_buffer.handle)

    #Draw a plabe using the texture the scene was rendered to
    hg.SetViewPerspective(view_id, 0, 0, res_x, res_y, hg.TranslationMat4(hg.Vec3(0, 0, -1.8)))

    val_uniforms = [hg.MakeUniformSetValue('color', hg.Vec4(1, 1, 1, 1))]
    tex_uniforms = [hg.MakeUniformSetTexture('s_tex', tex_color, 0)]

    hg.DrawModel(view_id, plane_mdl, plane_prg, val_uniforms, tex_uniforms,
        hg.TransformationMat4(hg.Vec3(0, 0, 0), hg.Vec3(math.pi / 2, 0, math.pi)))
    
    # Change state to capture when user press Space and Capture is not already running
    if (hg.ReadKeyboard().Key(hg.K_Space) and state == "none"):
        state = "capture"
        frame_count_capture, view_id = hg.CaptureTexture(view_id, res, tex_color_ref, tex_readback, picture)

    # Take screenshot if CaptureTexture is ready and user pressed space
    elif(state == "capture" and frame_count_capture <= frame):
        png_filename = "capture" + ".png"
        hg.SavePNG(picture, png_filename)
        state = "none" #Reset state to none to be able to screenshot again

    #
    frame = hg.Frame()
    hg.UpdateWindow(win)

hg.RenderShutdown()
hg.DestroyWindow(win)