Shader-code style prompt for a fantasy sphere book world

2x2 grid, 16:9, do this for 4 non copyrighted, public space books // Sphere SDF float sdf_sphere = sdSphere(p, 1.0); // Crack: a noise-modulated cutting plane that splits the sphere float crack = fbm(p) > 0.5 ? 1.0 : 0.0; // left/right // Outer left shell: displace sdf slightly for manuscript relief, then shade with cultural texture. float sdf_exterior = sdf_sphere; // left side only // Interior: carve a hollow region by subtracting a smaller sphere offset, leaving a shell. float sdf_cavern = sdSubtract(sdf_sphere, sdSphere(p - vec3(0.4,0,0), 0.8)); // hollow right side // Tiered architecture: series of nested boxes and cylinders placed along the cavern walls float sdf_arch = tiered_structures(p, epic_cities); // Creatures: SDFs of mythical beasts placed dynamically. float sdf_river = thin_tube(p, epic_river_path); // Soldiers: instanced tiny humanoid SDFs with armor, in formations. // Materials: manuscript = diffuse + normal map from calligraphy brush strokes; architecture = stone/gold PBR; interior light = emissive fire. // Lighting: point light deep inside cavern (fire), area light for studio. // Camera: macro lens, f/2.0, focus on cavern middle, DOF blur background and outer shell edges. // Post: shallow DOF, white studio beyond sphere, no modern elements.