• Interactive Poisson Blending on GPU
    Interactive Poisson Blending on GPU
  • 404 Not Found In Two Triangles
    404 Not Found In Two Triangles
  • Simplest and Fastest GLSL Edge Detection using Fwidth
    Simplest and Fastest GLSL Edge Detection using Fwidth

Tag: GPGPU

Unified Gnomonic and Stereographic Projections

Gnomonic projection, or rectilinear projection, together with stereographic projection, are two most commonly used projection in rendering 360 degree videos, or other VR applications. Recently, I found the inverse converting function from screen coordinates to the two projections can be unified within a single function. It’s not really surprising since both projection uses spherical lens,…


Equirectangular Projection, Gnomonic Projection, and Cubemaps

Gnomonic Projection Background According to MathWorld, the gnomonic projection is a nonconformal map projection obtained by projecting points (or ) on the surface of sphere from a sphere’s center O to point P in a plane that is tangent to a point S (Coxeter 1969, p. 93). In a gnomonic projection, great circles are mapped…


Interactive Poisson Blending on GPU

Recently, I have implemented two fragment shaders for interactive Poisson Blending (seamless blending).  Here is my real-time demo and code on ShaderToy: Press 1 for normal mode, press 2 for mixed gradients, press space to clear the canvas. Technical Brief I followed a simplified routine of the Poisson Image Editing paper [P. Pérez, M. Gangnet,…