Files
tinyusdz/examples/sdlviewer/simple-render.hh
2024-08-07 06:04:00 +09:00

430 lines
11 KiB
C++

#pragma once
#include <unordered_map>
#include "nanort.h"
#include "nanosg.h"
//
#include "tinyusdz.hh"
#include "tydra/render-data.hh"
namespace example {
// GLES-like naming
using vec3 = tinyusdz::value::float3;
using vec2 = tinyusdz::value::float2;
using mat2 = tinyusdz::value::matrix2f;
template<typename T>
inline void lerp(T dst[3], const T v0[3], const T v1[3], const T v2[3], float u, float v) {
dst[0] = (static_cast<T>(1.0) - u - v) * v0[0] + u * v1[0] + v * v2[0];
dst[1] = (static_cast<T>(1.0) - u - v) * v0[1] + u * v1[1] + v * v2[1];
dst[2] = (static_cast<T>(1.0) - u - v) * v0[2] + u * v1[2] + v * v2[2];
}
template <typename T>
inline T vlength(const T v[3]) {
const T d = v[0] * v[0] + v[1] * v[1] + v[2] * v[2];
if (std::fabs(d) > std::numeric_limits<T>::epsilon()) {
return std::sqrt(d);
} else {
return static_cast<T>(0.0);
}
}
template <typename T>
inline void vnormalize(T dst[3], const T v[3]) {
dst[0] = v[0];
dst[1] = v[1];
dst[2] = v[2];
const T len = vlength(v);
if (std::fabs(len) > std::numeric_limits<T>::epsilon()) {
const T inv_len = static_cast<T>(1.0) / len;
dst[0] *= inv_len;
dst[1] *= inv_len;
dst[2] *= inv_len;
}
}
template <typename T>
inline void vcross(T dst[3], const T a[3], const T b[3]) {
dst[0] = a[1] * b[2] - a[2] * b[1];
dst[1] = a[2] * b[0] - a[0] * b[2];
dst[2] = a[0] * b[1] - a[1] * b[0];
}
template <typename T>
inline void vsub(T dst[3], const T a[3], const T b[3]) {
dst[0] = a[0] - b[0];
dst[1] = a[1] - b[1];
dst[2] = a[2] - b[2];
}
template<typename T>
inline void calculate_normal(T Nn[3], const T v0[3], const T v1[3], const T v2[3]) {
T v10[3];
T v20[3];
vsub(v10, v1, v0);
vsub(v20, v2, v0);
T N[3];
vcross(N, v20, v10);
vnormalize(Nn, N);
}
struct AOV {
size_t width;
size_t height;
std::vector<float> rgb; // 3 x width x height
std::vector<float> shading_normal; // 3 x width x height
std::vector<float> geometric_normal; // 3 x width x height
std::vector<float> texcoords; // 2 x width x height
void Resize(size_t w, size_t h) {
width = w;
height = h;
rgb.resize(width * height * 3);
memset(rgb.data(), 0, sizeof(float) * rgb.size());
shading_normal.resize(width * height * 3);
memset(shading_normal.data(), 0, sizeof(float) * shading_normal.size());
geometric_normal.resize(width * height * 3);
memset(geometric_normal.data(), 0, sizeof(float) * geometric_normal.size());
texcoords.resize(width * height * 2);
memset(texcoords.data(), 0, sizeof(float) * texcoords.size());
}
};
struct Camera {
float eye[3] = {0.0f, 0.0f, 25.0f};
float up[3] = {0.0f, 1.0f, 0.0f};
float look_at[3] = {0.0f, 0.0f, 0.0f};
float quat[4] = {0.0f, 0.0f, 0.0f, 1.0f};
float fov = 60.0f; // in degree
};
template <typename T>
struct Buffer {
size_t num_coords{1}; // e.g. 3 for vec3 type.
std::vector<T> data;
};
//
// Renderable Node class for NanoSG. Includes xform
//
struct DrawNode {
std::array<float, 3> translation{0.0f, 0.0f, 0.0f};
std::array<float, 3> rotation{0.0f, 0.0f, 0.0f}; // euler rotation
std::array<float, 3> scale{1.0f, 1.0f, 1.0f};
};
//
// Mesh class used in NanoRT/NanoSG.
// Currently mesh data must be triangulated and all attributes are facevarying.
//
template<typename T>
struct DrawGeomMesh {
DrawGeomMesh() {}
///
/// Required accessor API for NanoSG
///
const float *GetVertices() const {
return nullptr; // TODO
//return reinterpret_cast<const float *>(ref_mesh->points.data());
}
const unsigned int *GetFaces() const {
return facevertex_indices.data();
}
size_t GetVertexStrideBytes() const { return sizeof(float) * 3; }
///
/// Get the geometric normal and the shading normal at `face_idx' th face.
///
void GetNormal(float Ng[3], float Ns[3], const unsigned int face_idx, const float u, const float v) const {
// Compute geometric normal.
unsigned int f0, f1, f2;
float v0[3], v1[3], v2[3];
f0 = facevertex_indices[3 * face_idx + 0];
f1 = facevertex_indices[3 * face_idx + 1];
f2 = facevertex_indices[3 * face_idx + 2];
v0[0] = vertices[3 * f0 + 0];
v0[1] = vertices[3 * f0 + 1];
v0[2] = vertices[3 * f0 + 2];
v1[0] = vertices[3 * f1 + 0];
v1[1] = vertices[3 * f1 + 1];
v1[2] = vertices[3 * f1 + 2];
v2[0] = vertices[3 * f2 + 0];
v2[1] = vertices[3 * f2 + 1];
v2[2] = vertices[3 * f2 + 2];
calculate_normal(Ng, v0, v1, v2);
if (vertex_normals.size() > 0) {
uint32_t v0 = facevertex_indices[3 * face_idx];
uint32_t v1 = facevertex_indices[3 * face_idx];
uint32_t v2 = facevertex_indices[3 * face_idx];
float n0[3], n1[3], n2[3];
n0[0] = vertex_normals[3 * v0 + 0];
n0[1] = vertex_normals[3 * v0 + 1];
n0[2] = vertex_normals[3 * v0 + 2];
n1[0] = vertex_normals[3 * v1 + 0];
n1[1] = vertex_normals[3 * v1 + 1];
n1[2] = vertex_normals[3 * v1 + 2];
n2[0] = vertex_normals[3 * v2 + 0];
n2[1] = vertex_normals[3 * v2 + 1];
n2[2] = vertex_normals[3 * v2 + 2];
lerp(Ns, n0, n1, n2, u, v);
} else if (facevarying_normals.size() > 0) {
float n0[3], n1[3], n2[3];
n0[0] = facevarying_normals[9 * face_idx + 0];
n0[1] = facevarying_normals[9 * face_idx + 1];
n0[2] = facevarying_normals[9 * face_idx + 2];
n1[0] = facevarying_normals[9 * face_idx + 3];
n1[1] = facevarying_normals[9 * face_idx + 4];
n1[2] = facevarying_normals[9 * face_idx + 5];
n2[0] = facevarying_normals[9 * face_idx + 6];
n2[1] = facevarying_normals[9 * face_idx + 7];
n2[2] = facevarying_normals[9 * face_idx + 8];
lerp(Ns, n0, n1, n2, u, v);
} else {
// Use geometric normal.
Ns[0] = Ng[0];
Ns[1] = Ng[1];
Ns[2] = Ng[2];
}
}
///
/// Get texture coordinate at `face_idx' th face.
///
void GetTexCoord(float tcoord[3], const unsigned int face_idx, const float u, const float v) {
if (vertex_uvs.size() > 0) {
uint32_t v0 = facevertex_indices[3 * face_idx];
uint32_t v1 = facevertex_indices[3 * face_idx];
uint32_t v2 = facevertex_indices[3 * face_idx];
float t0[3], t1[3], t2[3];
t0[0] = facevarying_uvs[6 * face_idx + 0];
t0[1] = facevarying_uvs[6 * face_idx + 1];
t0[2] = static_cast<T>(0.0);
t1[0] = facevarying_uvs[6 * face_idx + 2];
t1[1] = facevarying_uvs[6 * face_idx + 3];
t1[2] = static_cast<T>(0.0);
t2[0] = facevarying_uvs[6 * face_idx + 4];
t2[1] = facevarying_uvs[6 * face_idx + 5];
t2[2] = static_cast<T>(0.0);
lerp(tcoord, t0, t1, t2, u, v);
} else if (facevarying_uvs.size() > 0) {
float t0[3], t1[3], t2[3];
t0[0] = facevarying_uvs[6 * face_idx + 0];
t0[1] = facevarying_uvs[6 * face_idx + 1];
t0[2] = static_cast<T>(0.0);
t1[0] = facevarying_uvs[6 * face_idx + 2];
t1[1] = facevarying_uvs[6 * face_idx + 3];
t1[2] = static_cast<T>(0.0);
t2[0] = facevarying_uvs[6 * face_idx + 4];
t2[1] = facevarying_uvs[6 * face_idx + 5];
t2[2] = static_cast<T>(0.0);
lerp(tcoord, t0, t1, t2, u, v);
} else {
tcoord[0] = static_cast<T>(0.0);
tcoord[1] = static_cast<T>(0.0);
tcoord[2] = static_cast<T>(0.0);
}
}
///
/// ---
///
std::vector<float> vertices; // vec3f
std::vector<uint32_t>
facevertex_indices; // triangulated indices. 3 x num_faces
std::vector<float> vertex_normals; // 'vertex'-varying normals. 3 x 3 x num_verts
std::vector<float> facevarying_normals; // 3 x 3 x num_faces
std::vector<float> vertex_uvs; // 2 x 3 x num_verts
std::vector<float> facevarying_uvs; // 2 x 3 x num_faces
// arbitrary primvars(including texcoords(float2))
std::vector<Buffer<float>> float_primvars;
std::map<std::string, size_t>
float_primvars_map; // <name, index to `float_primvars`>
// arbitrary primvars in int type(e.g. texcoord indices(int3))
std::vector<Buffer<int32_t>> int_primvars;
std::map<std::string, size_t>
int_primvars_map; // <name, index to `int_primvars`>
int material_id{-1}; // per-geom material. index to `RenderScene::materials`
float world_matrix[4][4];
//nanort::BVHAccel<float> accel;
};
template<typename T>
struct UVReader {
static_assert(std::is_same<T, float>::value || std::is_same<T, vec2>::value || std::is_same<T, vec3>::value,
"Unsupported type for UVReader");
int32_t st_id{-1}; // index to DrawGeomMesh::float_primvars
int32_t indices_id{-1}; // index to DrawGeomMesh::int_primvars
mat2 uv_transform;
// Fetch interpolated UV coordinate
T fetch_uv(size_t face_id, float varyu, float varyv);
};
struct Texture {
enum Channel {
TEXTURE_CHANNEL_R,
TEXTURE_CHANNEL_G,
TEXTURE_CHANNEL_B,
TEXTURE_CHANNEL_RGB,
TEXTURE_CHANNEL_RGBA,
};
UVReader<vec2> uv_reader;
int32_t image_id{-1};
// NOTE: for single channel(e.g. R), [0] will be filled for the return value.
std::array<float, 4> fetch(size_t face_id, float varyu, float varyv,
Channel channel);
};
// https://graphics.pixar.com/usd/release/spec_usdpreviewsurface.html#texture-reader
// https://learn.foundry.com/modo/901/content/help/pages/uving/udim_workflow.html
// Up to 10 tiles for U direction.
// Not sure there is an limitation for V direction. Anyway maximum tile id is
// 9999.
#if 0
static uint32_t GetUDIMTileId(uint32_t u, uint32_t v)
{
uint32_t uu = std::max(1u, std::min(10u, u+1)); // clamp U dir.
return 1000 + v * 10 + uu;
}
#endif
struct UDIMTexture {
UVReader<vec2> uv_reader;
std::unordered_map<uint32_t, int32_t>
images; // key: udim tile_id, value: image_id
// NOTE: for single channel(e.g. R), [0] will be filled for the return value.
std::array<float, 4> fetch(size_t face_id, float varyu, float varyv,
Texture::Channel channel);
};
// base color(fallback color) or Texture
template <typename T>
struct ShaderParam {
ShaderParam(const T &t) { value = t; }
T value;
int32_t texture_id{-1};
};
// UsdPreviewSurface
struct PreviewSurfaceShader {
bool useSpecularWorkFlow{false};
ShaderParam<vec3> diffuseColor{{0.18f, 0.18f, 0.18f}};
ShaderParam<float> metallic{0.0f};
ShaderParam<float> roughness{0.5f};
ShaderParam<float> clearcoat{0.0f};
ShaderParam<float> clearcoatRoughness{0.01f};
ShaderParam<float> opacity{1.0f};
ShaderParam<float> opacityThreshold{0.0f};
ShaderParam<float> ior{1.5f};
ShaderParam<vec3> normal{{0.0f, 0.0f, 1.0f}};
ShaderParam<float> displacement{0.0f};
ShaderParam<float> occlusion{0.0f};
};
struct Material {
PreviewSurfaceShader shader;
};
// Simple LDR texture
struct Image {
std::vector<uint8_t> image;
int32_t width{-1};
int32_t height{-1};
int32_t channels{-1}; // e.g. 3 for RGB.
};
class RTRenderScene {
public:
std::vector<DrawGeomMesh<float>> draw_meshes;
std::vector<Material> materials;
std::vector<Texture> textures;
std::vector<Image> images;
// <precision, ptr to mesh class>
//std::vector<nanosg::Node<float, DrawGeomMesh>> nodes;
nanosg::Scene<float, DrawGeomMesh<float>> scene;
bool SetupFromUSDFile(const std::string &usd_filename, std::string &warn, std::string &err);
};
bool Render(const RTRenderScene &scene, const Camera &cam, AOV *output);
// Render images for lines [start_y, end_y]
// single-threaded. for webassembly.
bool RenderLines(int start_y, int end_y, const RTRenderScene &scene,
const Camera &cam, AOV *output);
} // namespace example