This interactive WebGL visualization reprojects a 360-degree equirectangular panorama image into the stereographic projection, enabling smooth zoom and pan interactions. It displays the source panorama as a textured plane, with the fragment shader performing inverse stereographic projection and rotation calculations in real time. The implementation uses d3.v3 for DOM and event handling, while raw WebGL shaders manage the rendering pipeline, including a custom vertex-fragment shader pair and texture mipmapping. The code compiles shaders, sets up a position buffer for a fullscreen quad, and updates uniform variables for translation, scale, and rotation based on user input.