Oxenfree II: Lost Signals provides a haunting, supernatural atmosphere. To achieve this, we combined mathematical screen distortion, geometric masking, and aggressive camera manipulation over the game's traditional 2.5D art style. The portal sequence uses several techniques to create these reality-bending visuals:
1. Portal Tear – The portal itself is portrayed as a window into the past. To give the geometric shape an otherworldly feel, we used stencil shaders so that the GPU only renders the "past timeline" layer inside the boundaries of that shape.
2. Radio Beams – The beam vectors are driven by Unity’s Line Renderer components. When untuned, sine waves and Perlin noise make the lines fluctuate like an oscilloscope; when you find the right frequency, mathematical interpolation (Lerp) snaps the lines perfectly straight.
3. Analog Screen Glitches – Screen-space distortion is achieved through chromatic aberration (for a dizzying look) and UV offsets (randomly snapping pixels horizontally to create a VHS-style glitch).
4. Environmental FX – Several added environmental effects accentuate the impact of the sequence, such as heavy camera shake, floating particles, and shockwaves.