Adding lua scene description

RayTracer/applications/SceneLoad.cpp

@@ -0,0 +1,151 @@
+
+#include "Rayt.hpp"
+
+extern "C" {
+#include "lauxlib.h"
+#include "lualib.h"
+}
+
+#include "OBJ_Loader.h"
+
+bool loadMeshes(tp::Scene& scene, const tp::String& objetsPath) {
+  using namespace tp;
+
+  objl::Loader Loader;
+
+  if (!Loader.LoadFile(objetsPath.read())) {
+    std::cout << "Failed to Load File. May have failed to find it or it was not an .obj file.\n";
+    return false;
+  }
+
+  for (auto& curMesh : Loader.LoadedMeshes) {
+    scene.mObjects.append(Topology());
+    auto object = &scene.mObjects.last();
+
+    for (int j = 0; j < curMesh.Indices.size(); j += 3) {
+      unsigned int idx1 = curMesh.Indices[j];
+      unsigned int idx2 = curMesh.Indices[j + 1];
+      unsigned int idx3 = curMesh.Indices[j + 2];
+
+      Vec3F v1 = {curMesh.Vertices[idx1].Position.X, curMesh.Vertices[idx1].Position.Y, curMesh.Vertices[idx1].Position.Z};
+      Vec3F v2 = {curMesh.Vertices[idx2].Position.X, curMesh.Vertices[idx2].Position.Y, curMesh.Vertices[idx2].Position.Z};
+      Vec3F v3 = {curMesh.Vertices[idx3].Position.X, curMesh.Vertices[idx3].Position.Y, curMesh.Vertices[idx3].Position.Z};
+
+      object->addTrig(v1, v2, v3);
+    }
+    object->updateTransformed();
+  }
+
+  return scene.mObjects.size();
+}
+
+bool getVector(lua_State* L, const char* name, tp::Vec3F& out, const char* parent) {
+  lua_getglobal(L, name);
+
+  if (lua_istable(L, -1)) {
+    lua_pushstring(L, "x");
+    lua_gettable(L, -2);
+
+    if (lua_isnumber(L, -1)) {
+      out.x = lua_tonumber(L, -1);
+    } else {
+      printf("Component of vector '%s' is not found in %s\n\n", name, parent);
+      return false;
+    }
+
+    lua_pop(L, 1);
+
+  } else {
+    printf("Vector '%s' is not found in %s\n\n", name, parent);
+    return false;
+  }
+}
+
+void loadScene(tp::Scene& scene, const tp::String& scenePath, tp::RayTracer::RenderSettings& settings) {
+  lua_State* L = luaL_newstate();
+  luaL_openlibs(L);
+
+  if (luaL_dofile(L, "script.lua") != 0) {
+    lua_close(L);
+    printf("Cant open scene script.\n");
+    return;
+  }
+
+  lua_getglobal(L, "Meshes");
+
+  if (lua_isstring(L, -1)) {
+    tp::String meshesPath = lua_tostring(L, -1);
+
+    if (!loadMeshes(scene, meshesPath)) {
+      printf("No 'meshes' loaded - check ur .obj path and validate content of .obj .\n");
+      return;
+    }
+
+  } else {
+    printf("No 'meshes' path given.\n");
+    return;
+  }
+
+  // --- camera
+
+  // Access Camera table
+  lua_getglobal(L, "Camera");
+  if (!lua_istable(L, -1)) {
+    printf("Camera is not a table.\n");
+    lua_close(L);
+    return;
+  }
+
+  // Verify you are inside the "Camera" table
+  int cameraTableIndex = lua_gettop(L); // Get the index of the "Camera" table
+
+  // Access the "pos" field and validate it
+  lua_getfield(L, cameraTableIndex, "pos");
+  if (!lua_istable(L, -1) || lua_rawlen(L, -1) != 3) {
+    printf("Invalid 'pos' field in Camera table.\n");
+    lua_close(L);
+    return;
+  }
+
+  // Read the values from the table
+  float pos[3];
+  for (int i = 0; i < 3; i++) {
+    lua_rawgeti(L, -1, i + 1);
+    if (lua_isnumber(L, -1)) {
+      pos[i] = lua_tonumber(L, -1);
+    } else {
+      printf("Invalid 'pos' field value at index %d.\n", i + 1);
+      lua_close(L);
+      return;
+    }
+    lua_pop(L, 1);
+  }
+
+  // Access the "size_x" field and validate it
+  lua_getfield(L, cameraTableIndex, "size_x");
+  if (!lua_isnumber(L, -1)) {
+    printf("Invalid or missing 'size_x' field in Camera table.\n");
+    lua_close(L);
+    return;
+  }
+  int size_x = lua_tointeger(L, -1);
+  lua_pop(L, 1); // Pop the 'size_x' value from the stack
+
+  // Access the "size_y" field and validate it
+  lua_getfield(L, cameraTableIndex, "size_y");
+  if (!lua_isnumber(L, -1)) {
+    printf("Invalid or missing 'size_y' field in Camera table.\n");
+    lua_close(L);
+    return;
+  }
+  int size_y = lua_tointeger(L, -1);
+
+  settings.size = {(tp::halnf) size_x, (tp::halnf) size_y};
+
+  scene.mCamera.lookAtPoint({0, 0, 0}, {pos[0], pos[1], pos[2]}, {0, 0, 1});
+  scene.mCamera.setFOV(3.14 / 4);
+  scene.mCamera.setFar(100);
+  scene.mCamera.setRatio((tp::halnf) size_x / (tp::halnf) size_y);
+
+  lua_close(L);
+}