Was just wondering how I would go about creating a planar shadow from a 4×3 matrix, all online demos I’ve seen use 4×4 matrices instead.
Share
Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
Was just wondering how I would go about creating a planar shadow from a 4×3 matrix, all online demos I’ve seen use 4×4 matrices instead.
I guess that this is done by projecting a 3D object onto a plane, which essentially needs a fourth coordinate to represent infinity. If you only use 3 coordinates, you can only represent |R^3. However, for projections like shadows you will need full 3-space, thus including infinity – so you need the fourth coordinate.
I guess you can solve this with trigonometry and not matrices at all.
What is it you are trying to accomplish?