Files
HelloVulkan/Lib/meshoptimizer/gltf/encodebasis.cpp
T
atdunbg 5bdfb53566 feat: LOD 网格分级——meshopt 解析期简化 + 按距离/级联选级
vendored meshoptimizer 1.2(submodule 环境故障改直接 vendor)。Mesh
多 LOD:各级索引连续拼进同一 index buffer(共享顶点,LodRange 区间
选择),解析期 meshopt_simplify 生成链(LOD0=原始,每级目标减半,
相对误差 1e-2,小网格复用上级);都在 worker 线程,加载零额外卡顿。

SceneRenderer 按 (mesh, LOD) 聚合 batch(lookup key = 指针<<8|lod):
主视图按屏占比近似 radius/dist 选级(阈值 10/20 倍半径);阴影级联
按级联序降级(越远越简)。Draw 按 batch.lod 选索引区间。

A/B 对比(100 背包 10×10,RTX 5060 Laptop,vsync off):
- 纯背包:LOD 开 93-95 fps / 关 90-107 fps —— 无显著差异
- 加 SunTemple:LOD 开 52-56 / 关 51-55 —— 无显著差异
结论:当前场景瓶颈不在顶点数(5060 顶点吞吐富余),LOD 基础设施
保留(几何复杂资产/低端 GPU/更大场景生效),帧率问题转向 Tracy
GPU 时间线定位真实瓶颈。

坑:LodRange 记录"LOD 不足复用最后一级"时 first 不得继续累加
(buffer 无重复数据,累加必越界——VUID-08798 抓的)。
2026-09-24 20:53:19 +08:00

215 lines
6.7 KiB
C++

// This file is part of gltfpack; see gltfpack.h for version/license details
#ifdef WITH_BASISU
#include "gltfpack.h"
#define BASISU_NO_ITERATOR_DEBUG_LEVEL
#ifdef __clang__
#pragma GCC diagnostic ignored "-Wunknown-warning-option"
#pragma GCC diagnostic ignored "-Warray-bounds"
#pragma GCC diagnostic ignored "-Wc++17-extensions"
#pragma GCC diagnostic ignored "-Wdeprecated-builtins"
#endif
#ifdef __GNUC__
#pragma GCC diagnostic ignored "-Wclass-memaccess"
#pragma GCC diagnostic ignored "-Wshadow"
#pragma GCC diagnostic ignored "-Wunused-local-typedefs"
#pragma GCC diagnostic ignored "-Wunused-value"
#endif
#if defined(__GNUC__) && __GNUC__ >= 12
#pragma GCC diagnostic ignored "-Wc++17-extensions"
#endif
#include "encoder/basisu_comp.h"
struct BasisSettings
{
int etc1s_l;
int etc1s_q;
int uastc_l;
float uastc_q;
};
static const BasisSettings kBasisSettings[10] = {
{1, 1, 0, 4.f},
{1, 32, 0, 3.f},
{1, 64, 1, 2.f},
{1, 96, 1, 1.5f},
{1, 128, 1, 1.f}, // quality arguments aligned with basisu defaults
{1, 150, 1, 0.8f},
{1, 170, 1, 0.6f},
{1, 192, 1, 0.4f}, // gltfpack defaults
{1, 224, 2, 0.2f},
{1, 255, 2, 0.f},
};
static void fillParams(basisu::basis_compressor_params& params, const char* input, const char* output, bool uastc, int width, int height, const BasisSettings& bs, const ImageInfo& info, const Settings& settings)
{
if (uastc)
{
static const uint32_t s_level_flags[basisu::TOTAL_PACK_UASTC_LEVELS] = {basisu::cPackUASTCLevelFastest, basisu::cPackUASTCLevelFaster, basisu::cPackUASTCLevelDefault, basisu::cPackUASTCLevelSlower, basisu::cPackUASTCLevelVerySlow};
params.m_uastc = true;
#if BASISU_LIB_VERSION >= 160
params.m_pack_uastc_ldr_4x4_flags &= ~basisu::cPackUASTCLevelMask;
params.m_pack_uastc_ldr_4x4_flags |= s_level_flags[bs.uastc_l];
params.m_rdo_uastc_ldr_4x4 = bs.uastc_q > 0;
params.m_rdo_uastc_ldr_4x4_quality_scalar = bs.uastc_q;
params.m_rdo_uastc_ldr_4x4_dict_size = 1024;
#else
params.m_pack_uastc_flags &= ~basisu::cPackUASTCLevelMask;
params.m_pack_uastc_flags |= s_level_flags[bs.uastc_l];
params.m_rdo_uastc = bs.uastc_q > 0;
params.m_rdo_uastc_quality_scalar = bs.uastc_q;
params.m_rdo_uastc_dict_size = 1024;
#endif
}
else
{
#if BASISU_LIB_VERSION >= 200
params.m_etc1s_compression_level = bs.etc1s_l;
params.m_quality_level = bs.etc1s_q;
params.m_etc1s_max_endpoint_clusters = 0;
params.m_etc1s_max_selector_clusters = 0;
#elif BASISU_LIB_VERSION >= 160
params.m_compression_level = bs.etc1s_l;
params.m_etc1s_quality_level = bs.etc1s_q;
params.m_etc1s_max_endpoint_clusters = 0;
params.m_etc1s_max_selector_clusters = 0;
#else
params.m_compression_level = bs.etc1s_l;
params.m_quality_level = bs.etc1s_q;
params.m_max_endpoint_clusters = 0;
params.m_max_selector_clusters = 0;
#endif
params.m_no_selector_rdo = info.normal_map;
params.m_no_endpoint_rdo = info.normal_map;
}
params.m_perceptual = info.srgb;
params.m_mip_gen = true;
params.m_mip_srgb = info.srgb;
params.m_resample_width = width;
params.m_resample_height = height;
params.m_y_flip = settings.texture_flipy;
params.m_create_ktx2_file = true;
#if BASISU_LIB_VERSION >= 200
params.m_ktx2_and_basis_srgb_transfer_function = info.srgb;
#else
params.m_ktx2_srgb_transfer_func = info.srgb;
#endif
if (uastc)
{
params.m_ktx2_uastc_supercompression = basist::KTX2_SS_ZSTANDARD;
params.m_ktx2_zstd_supercompression_level = 9;
}
params.m_read_source_images = true;
#if BASISU_LIB_VERSION >= 150
params.m_write_output_basis_or_ktx2_files = true;
#else
params.m_write_output_basis_files = true;
#endif
params.m_source_filenames.resize(1);
params.m_source_filenames[0] = input;
params.m_out_filename = output;
params.m_status_output = false;
}
static const char* prepareEncode(basisu::basis_compressor_params& params, const cgltf_image& image, const char* input_path, const ImageInfo& info, const Settings& settings, const std::string& temp_prefix, std::string& temp_input, std::string& temp_output)
{
std::string img_data;
std::string mime_type;
if (!readImage(image, input_path, img_data, mime_type))
return "error reading source file";
if (mime_type != "image/png" && mime_type != "image/jpeg")
return NULL;
int width = 0, height = 0;
if (!getDimensions(img_data, mime_type.c_str(), width, height))
return "error parsing image header";
adjustDimensions(width, height, settings.texture_scale[info.kind], settings.texture_limit[info.kind], settings.texture_pow2);
temp_input = temp_prefix + mimeExtension(mime_type.c_str());
temp_output = temp_prefix + ".ktx2";
if (!writeFile(temp_input.c_str(), img_data))
return "error writing temporary file";
int quality = settings.texture_quality[info.kind];
bool uastc = settings.texture_mode[info.kind] == TextureMode_UASTC;
const BasisSettings& bs = kBasisSettings[quality - 1];
fillParams(params, temp_input.c_str(), temp_output.c_str(), uastc, width, height, bs, info, settings);
return NULL;
}
void encodeImagesBasis(std::string* encoded, const cgltf_data* data, const std::vector<ImageInfo>& images, const char* input_path, const Settings& settings)
{
basisu::basisu_encoder_init();
basisu::vector<basisu::basis_compressor_params> params(data->images_count);
basisu::vector<basisu::parallel_results> results(data->images_count);
std::string temp_prefix = getTempPrefix();
std::vector<std::string> temp_inputs(data->images_count);
std::vector<std::string> temp_outputs(data->images_count);
for (size_t i = 0; i < data->images_count; ++i)
{
const cgltf_image& image = data->images[i];
ImageInfo info = images[i];
if (settings.texture_mode[info.kind] == TextureMode_ETC1S || settings.texture_mode[info.kind] == TextureMode_UASTC)
if (const char* error = prepareEncode(params[i], image, input_path, info, settings, temp_prefix + "-" + std::to_string(i), temp_inputs[i], temp_outputs[i]))
encoded[i] = error;
}
uint32_t num_threads = settings.texture_jobs == 0 ? std::thread::hardware_concurrency() : settings.texture_jobs;
basisu::basis_parallel_compress(num_threads, params, results);
for (size_t i = 0; i < data->images_count; ++i)
{
if (params[i].m_source_filenames.empty())
; // encoding was skipped or preparation resulted in an error
else if (results[i].m_error_code == basisu::basis_compressor::cECFailedReadingSourceImages)
encoded[i] = "error decoding source image";
else if (results[i].m_error_code != basisu::basis_compressor::cECSuccess)
encoded[i] = "error encoding image";
else if (!readFile(temp_outputs[i].c_str(), encoded[i]))
encoded[i] = "error reading temporary file";
}
for (size_t i = 0; i < data->images_count; ++i)
{
if (!temp_inputs[i].empty())
removeFile(temp_inputs[i].c_str());
if (!temp_outputs[i].empty())
removeFile(temp_outputs[i].c_str());
}
}
#endif