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playcanvas

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Open-source WebGL/WebGPU 3D engine for the web

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playcanvas/engine

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declare const _default: "\n\nuniform matrix_model: mat4x4f;\nuniform matrix_view: mat4x4f;\n#ifndef GSPLAT_CENTER_NOPROJ\n uniform camera_params: vec4f; // 1 / far, far, near, isOrtho\n uniform matrix_projection: mat4x4f;\n #ifdef GSPLAT_FISHEYE\n uniform fisheye_k: f32;\n uniform fisheye_inv_k: f32; // 1.0 / fisheye_k (precomputed on CPU)\n uniform fisheye_projMat00: f32; // projection scale X (precomputed on CPU)\n uniform fisheye_projMat11: f32; // projection scale Y (precomputed on CPU)\n #endif\n#endif\n\n// project the model space gaussian center to view and clip space\nfn initCenter(modelCenter: vec3f, center: ptr<function, SplatCenter>) -> bool {\n let modelView: mat4x4f = uniform.matrix_view * uniform.matrix_model;\n let centerView: vec4f = modelView * vec4f(modelCenter, 1.0);\n\n #ifndef GSPLAT_CENTER_NOPROJ\n\n #ifdef GSPLAT_FISHEYE\n\n // Generalized fisheye: g(\u03B8) = k\u00B7tan(\u03B8/k)\n // k=2: stereographic, k\u2192\u221E: equidistant\n let v: vec3f = centerView.xyz;\n let r_xy: f32 = length(v.xy);\n let neg_z: f32 = -v.z;\n let theta: f32 = atan2(r_xy, neg_z);\n\n // Cull near the singularity at \u03B8 = k\u00B7\u03C0/2, and at camera origin\n let maxTheta: f32 = min(uniform.fisheye_k * 1.5707963, 3.13);\n if (theta > maxTheta - 0.01 || dot(v, v) < 0.0001) {\n return false;\n }\n\n let tk: f32 = theta * uniform.fisheye_inv_k;\n let sin_tk: f32 = sin(tk);\n let cos_tk: f32 = cos(tk);\n let g_theta: f32 = uniform.fisheye_k * sin_tk / cos_tk;\n let fisheye_s: f32 = select(select(0.0, 1.0 / neg_z, neg_z > 0.0), g_theta / r_xy, r_xy > 1e-4);\n\n let ndc: vec2f = vec2f(uniform.fisheye_projMat00 * fisheye_s * v.x, uniform.fisheye_projMat11 * fisheye_s * v.y);\n\n let near: f32 = uniform.camera_params.z;\n let far: f32 = uniform.camera_params.y;\n let linearDepth: f32 = neg_z;\n let depthNdc: f32 = clamp((linearDepth - near) / (far - near), 0.0, 1.0);\n\n center.proj = vec4f(ndc, depthNdc, 1.0);\n center.projMat00 = uniform.fisheye_projMat00;\n center.fisheyeSinTK = sin_tk;\n center.fisheyeCosTK = cos_tk;\n center.fisheyeRxy = r_xy;\n\n #else\n\n // early out if splat is behind the camera (perspective only)\n // orthographic projections don't need this check as frustum culling handles it\n if (uniform.camera_params.w != 1.0 && centerView.z > 0.0) {\n return false;\n }\n\n var centerProj: vec4f = uniform.matrix_projection * centerView;\n\n // ensure gaussians are not clipped by camera near and far\n centerProj.z = clamp(centerProj.z, 0.0, abs(centerProj.w));\n\n center.proj = centerProj;\n center.projMat00 = uniform.matrix_projection[0][0];\n\n #endif\n\n #endif\n\n center.view = centerView.xyz / centerView.w;\n center.modelView = modelView;\n return true;\n}\n"; export default _default;