Exporting keyframe animation from Blender to Unigine

[angus]

To solve a need we had, the below code will copy Blender keyframe animation to a CSV file. It writes out location and rotation only. Data is stored as XYZ position, Quaternion rotation. Axis conversion is done in the script so the values from the CSV file can be used directly.

 

import bpy
import os
from math import degrees
from bpy_extras.io_utils import axis_conversion

def loc_rot_to_file(context, filepath):

    blender_to_unigine = axis_conversion(from_forward='-Y', 
                                         from_up='Z',
                                         to_forward='Y',
                                         to_up='Z').to_4x4()

    movement_object = bpy.context.selected_objects[0]
    mw =  movement_object.matrix_world
    scene = context.scene
    frame = scene.frame_start
    
    

    f = open(filepath, 'w', encoding='utf-8')
        
    
    while frame <= scene.frame_end:
        scene.frame_set(frame)
        
        mw =  movement_object.matrix_world
        mw = blender_to_unigine @ mw
        
        x, y, z = mw.to_translation()
        rw, rx, ry, rz = mw.to_quaternion() 
                
        f.write("%d" % frame)
        f.write(", ")
        f.write("%0.9f, %0.9f, %0.9f" % (x, y, z))
        f.write(", ")
        f.write("%0.9f, %0.9f, %0.9f, %0.9f" % (rw, rx, ry, rz))
        f.write("\n")
        frame += 1
    f.close()




loc_rot_to_file(bpy.context, "d:/tmp/blenderdata.csv")

 

To use, copy  the code in to the "Scripting" panel in Blender, select the object you wish to save out, edit the destination file name and then "Run Script" in Blender to save it out.

Warning: only lightly tested.

[leon.dong]

Thanks . angus ,

BTW , how to play keyframe animation in Unigine after export ?

 

[angus]

On 5/5/2020 at 10:49 AM, leon.dong said:

Thanks . angus ,

BTW , how to play keyframe animation in Unigine after export ?

 

I load the CSV file in to two Unigine Vectors. 

 

	std::ifstream infile(movement_filename_full.get());

	if (!infile) {
		Log::error("Error opening [%s]\n", movement_filename_full.get());
		assert(false);
	}
	   	
	int frame = 0;
	vec3 position;
	quat rotation;
	char comma;

	// File is CSV with frame number, location XYZ, rotation Quat. 
	while (infile >> frame >> comma >> position.x >> comma >> position.y >> comma >> position.z >> comma >> rotation.w >> comma >> rotation.x >> comma >> rotation.y >> comma >> rotation.z)
	{

		position *= scaling_factor;
		
		thing_positions.push_back((position));
		thing_rotations.push_back(rotation);
	
	}

 

And then at go-time it's just a case of setting location and rotation on the node

 

	thing->setWorldRotation(thing_rotations.at(frame_number));
	thing->setWorldPosition(thing_positions.at(frame_number));

 

Where "frame_number" increments in-line with the frame rate of the original Blender file by adding Game::getIFps() 

 

[leon.dong]

Thanks.