Questions tagged [animation]
The animation tag has no usage guidance.
2
votes
1answer
60 views
What noises can be sliced?
A well-known property of Perlin noise (with FBM) is that if you take a slice of it, the result is still Perlin noise. So, by taking successive slices of 4D noise, you get smoothly shifting 3D noise, ...
0
votes
1answer
83 views
Which techniques do I need to animate a 3D model in my homemade engine
Suppose I am making my own C++ 3D engine; I can already load a 3D model using assimp, display it with phong lighting, and I now want to animate it.
I'd like features in my engine to, say, load a run ...
1
vote
1answer
134 views
glTF animation keyframe question
I have an animated cube with 5 keyframes and when I export it to glTF with blender, in the file I can only see 3 keyframes:
But when I viewed the gltf model with viewer all 5 keyframes worked well ...
1
vote
1answer
27 views
compression of gif animation
I have a parchment animation at singingdays.co.uk that is a rather large file of about 80mb which obviously is taking a long time to download. I have managed to compress it down to about 60mb using ...
1
vote
0answers
32 views
kinematics and dynamics of a sphere in a spring mass system?
I am attempting to code a simple spring mass system simulation in which a sphere pendulus hangs from a string (a spring) by the top and then another sphere (controlled by the user) can move and ...
2
votes
0answers
44 views
Triangle-based and vertex-based skinning models?
I'm reading the Loper et al. 2015 paper on the Skinned Multi-Person Linear Model and I came across this:
What we would like is a vertex-based model that has the expressive
power of the triangle ...
1
vote
1answer
238 views
How can I use 3d animation to create a character that uses sign language?
I performed a quick search on programs that translate natural language to sign language (through a 3D animation character). Here are examples:
IBM SISI
ProDeaf (which is an android app)
My question ...
4
votes
1answer
152 views
Was Evans & Sutherland CT5 really created in 1981?
A few days ago I found a video on Twitter showing the Evans & Sutherland CT5 Flight Simulator system. It was labeled as 1981 footage and looked really amazing. The first time I saw similar 3D ...
3
votes
1answer
106 views
pseudoinverse Jacobian and adding more control in computer animation
I am studying inverse kinematics.
But I wonder the suggested equations.
(The following equations are taken from 'Computer Animation Algorithms and Techniques Third Edition Page, 181')
To better ...
1
vote
0answers
51 views
General interpolation practices
Say my animation scenario contains one mesh interpolating into another (possibly approximating over other meshes), using Bezier curves.
I know that for smooth surfaces, where normals can be ...
2
votes
0answers
44 views
Interpolating normals during animation
I'm doing linear tweening of a cyllinder to a cone of equal radius and height in OpenGL. I know parametric equations of both of them, so I derived vertex normals accordingly. Now, I know, that proper ...
1
vote
1answer
52 views
Is it possible to draw the intersection of two squares of known dimension using only x,y coordinates and without an if statement?
Say I have two squares, both 10x10, with some small, unknown overlap.
Is there a way to draw the intersection of these two squares using the width, height and x,y coordinates of each square, while ...
4
votes
0answers
88 views
How are fluid simulations handled in Computer Graphics?
How are fluid simulations handled in Computer Graphics? For a novice, there are hardly any novice friendly tutorials explaining how particles or fluids can be simulated.
Things like smoke, crown ...
4
votes
1answer
85 views
Need help reasoning about video oscillation >60hz
I want to make a basic video oscillator for the web. What I want to do is basically illustrated in a tutorial for Lumen: essentially, I want to define an oscillator to turn on and off a color signal ...
6
votes
2answers
705 views
Pixel dispersion (dissolving) algorithms
This YouTube video of a flip-dot display (physical b/w pixels) shows the reverse of an effect that might be called dissolve or dispersion, i.e. a text emerges from noise by pixels moving in to form ...
2
votes
1answer
205 views
Inverse Kinematics with more than 2 segments
I'm building a 2D inverse kinematics system and can't figure out how to find all the joint positions. I have the math to make a typical IK set up with a single bend (e.g. arm, leg), but I get stuck ...
1
vote
1answer
177 views
Calculating Skeleton-Deformed Mesh Normals
I'm implementing mesh skinning in a project of mine. I can calculate vertex positions based on bone transformations, but I've run into a problem with calculating their normals.
From the resources I'...
2
votes
0answers
59 views
smooth zoom animation formulas (and rounding numbers)
I need to generate an easy animation video in Python (I use PIL to create every frame, then combine them using avconv). The animation is just an image being zoomed ...
5
votes
1answer
92 views
How does a rigged model work?
What black magic is behind this?
Starting from a pile of polygons, a skeleton, and an initial conformation, how is a new conformation turned into a new pile of polygons?
4
votes
2answers
218 views
Storing 3D animations for ray tracing
I've just finished writing a path tracer that takes OBJ files and renders it. This is convenient for still images, but my end goal was to export a sequence from a 3D application (Blender was what I ...
5
votes
2answers
3k views
How to achieve gimbal lock with Euler angles?
I was studying about Euler angles and I came across the problem gimbal lock which can occur by using Euler angles. In gimbal lock we lose one axis of rotation.
But how? And when does it happen? On ...
1
vote
0answers
175 views
How to do keyframe interpolation on matlab?
I want to do keyframe interpolation in matlab.
If I understand correctly, it uses splines to approximate the the motion of specific pixel points within the frames(through transforms). Correct me if I'...
2
votes
0answers
134 views
Coordinate system transformation in motion capture files
I am trying to align two motion capture files from different sources.
The motion capture file consist of a skeleton specified as a hierarchy of joints. Each joint i.e. "shoulder" has three pieces of ...
6
votes
1answer
131 views
Questions about Preconditioning Conjugate Gradient method in Baraff & Witkin 98?
I encountered some problems when implementing the cloth simulation algorithm from Baraff & Witkin 98's Large Steps in Cloth Simulation.
Baraff & Witkin 98
Consider the cloth as a particle ...
4
votes
1answer
217 views
Spine. What is the name of the process?
https://www.youtube.com/watch?v=twUz99ek5do&list=WL&index=5
There is a process from 1:51, where the guy start making polygons around the bodyparts. I think this is this part is where (with ...
1
vote
1answer
64 views
How to design something like this? [closed]
I am very eager to know what technology might been used to implement this piece of wonder:
Any idea?
I think, it's ray tracing. What do you think?
1
vote
0answers
60 views
How is smooth animation accomplished? [closed]
How are objects moved smoothly from point A to point B given matrix transformations that describe next position?
4
votes
2answers
147 views
Software to compose separate models into an articulated model?
I've inherited a system which animates a humanoid avatar by loading various models and manually calculating transformations for each one. I'm in the process of porting part of this system to Three.js, ...
14
votes
1answer
166 views
How can I model distant rain?
Close up, rain can be modeled as transparent balls of water with appropriate motion blur. This seems impractical for large volumes, which would be necessary for scenes of rain in the distance.
At ...
