High poly 3D models flicker with complex shaders mainly due to z-fighting, shader precision limits, or overdraw.
- **Z-fighting**: Occurs when polygon surfaces are too close, confusing the GPU’s depth sorting (which surface to render first). - **Shader precision limits**: Low-precision variables (like half-floats) can’t handle detailed calculations for high poly geometry. - **Overdraw**: Happens with overlapping polygons or transparent layers, forcing the GPU to re-render areas repeatedly.
Fix it by checking for overlapping geometry, using higher-precision shader variables (e.g., float instead of half), or simplifying transparent layers.