declare const _default: "\n\nvec4 SampleTextureCatmullRom(TEXTURE_ACCEPT(tex), vec2 uv, vec2 texSize) {\n    // We're going to sample a a 4x4 grid of texels surrounding the target UV coordinate. We'll do this by rounding\n    // down the sample location to get the exact center of our \"starting\" texel. The starting texel will be at\n    // location [1, 1] in the grid, where [0, 0] is the top left corner.\n    vec2 samplePos = uv * texSize;\n    vec2 texPos1 = floor(samplePos - 0.5) + 0.5;\n\n    // Compute the fractional offset from our starting texel to our original sample location, which we'll\n    // feed into the Catmull-Rom spline function to get our filter weights.\n    vec2 f = samplePos - texPos1;\n\n    // Compute the Catmull-Rom weights using the fractional offset that we calculated earlier.\n    // These equations are pre-expanded based on our knowledge of where the texels will be located,\n    // which lets us avoid having to evaluate a piece-wise function.\n    vec2 w0 = f * (-0.5 + f * (1.0 - 0.5 * f));\n    vec2 w1 = 1.0 + f * f * (-2.5 + 1.5 * f);\n    vec2 w2 = f * (0.5 + f * (2.0 - 1.5 * f));\n    vec2 w3 = f * f * (-0.5 + 0.5 * f);\n\n    // Work out weighting factors and sampling offsets that will let us use bilinear filtering to\n    // simultaneously evaluate the middle 2 samples from the 4x4 grid.\n    vec2 w12 = w1 + w2;\n    vec2 offset12 = w2 / (w1 + w2);\n\n    // Compute the final UV coordinates we'll use for sampling the texture\n    vec2 texPos0 = (texPos1 - 1.0) / texSize;\n    vec2 texPos3 = (texPos1 + 2.0) / texSize;\n    vec2 texPos12 = (texPos1 + offset12) / texSize;\n\n    vec4 result = vec4(0.0);\n    result += texture2DLod(tex, vec2(texPos0.x, texPos0.y), 0.0) * w0.x * w0.y;\n    result += texture2DLod(tex, vec2(texPos12.x, texPos0.y), 0.0) * w12.x * w0.y;\n    result += texture2DLod(tex, vec2(texPos3.x, texPos0.y), 0.0) * w3.x * w0.y;\n\n    result += texture2DLod(tex, vec2(texPos0.x, texPos12.y), 0.0) * w0.x * w12.y;\n    result += texture2DLod(tex, vec2(texPos12.x, texPos12.y), 0.0) * w12.x * w12.y;\n    result += texture2DLod(tex, vec2(texPos3.x, texPos12.y), 0.0) * w3.x * w12.y;\n\n    result += texture2DLod(tex, vec2(texPos0.x, texPos3.y), 0.0) * w0.x * w3.y;\n    result += texture2DLod(tex, vec2(texPos12.x, texPos3.y), 0.0) * w12.x * w3.y;\n    result += texture2DLod(tex, vec2(texPos3.x, texPos3.y), 0.0) * w3.x * w3.y;\n\n    return result;\n}\n";
export default _default;