add gpu to bundle adjustment

Author: min-hieu-netropy

glomap/estimators/bundle_adjustment.cc

@@ -3,6 +3,8 @@
 #include <colmap/estimators/cost_functions.h>
 #include <colmap/estimators/manifold.h>
 #include <colmap/sensor/models.h>
+#include <colmap/util/cuda.h>
+#include <colmap/util/misc.h>
 
 namespace glomap {
 
@@ -36,6 +38,57 @@ bool BundleAdjuster::Solve(const ViewGraph& view_graph,
   // Set the solver options.
   ceres::Solver::Summary summary;
 
+  int num_images = images.size();
+#ifdef GLOMAP_CUDA_ENABLED
+  bool cuda_solver_enabled = false;
+
+#if (CERES_VERSION_MAJOR >= 3 ||                                \
+     (CERES_VERSION_MAJOR == 2 && CERES_VERSION_MINOR >= 2)) && \
+    !defined(CERES_NO_CUDA)
+  if (options_.use_gpu && num_images >= options_.min_num_images_gpu_solver) {
+    cuda_solver_enabled = true;
+    options_.solver_options.dense_linear_algebra_library_type = ceres::CUDA;
+  }
+#else
+  if (options_.use_gpu) {
+    LOG_FIRST_N(WARNING, 1)
+        << "Requested to use GPU for bundle adjustment, but Ceres was "
+           "compiled without CUDA support. Falling back to CPU-based dense "
+           "solvers.";
+  }
+#endif
+
+#if (CERES_VERSION_MAJOR >= 3 ||                                \
+     (CERES_VERSION_MAJOR == 2 && CERES_VERSION_MINOR >= 3)) && \
+    !defined(CERES_NO_CUDSS)
+  if (options_.use_gpu && num_images >= options_.min_num_images_gpu_solver) {
+    cuda_solver_enabled = true;
+    options_.solver_options.sparse_linear_algebra_library_type =
+        ceres::CUDA_SPARSE;
+  }
+#else
+  if (options_.use_gpu) {
+    LOG_FIRST_N(WARNING, 1)
+        << "Requested to use GPU for bundle adjustment, but Ceres was "
+           "compiled without cuDSS support. Falling back to CPU-based sparse "
+           "solvers.";
+  }
+#endif
+
+  if (cuda_solver_enabled) {
+    const std::vector<int> gpu_indices = colmap::CSVToVector<int>(options_.gpu_index);
+    THROW_CHECK_GT(gpu_indices.size(), 0);
+    colmap::SetBestCudaDevice(gpu_indices[0]);
+  }
+#else
+  if (options_.use_gpu) {
+    LOG_FIRST_N(WARNING, 1)
+        << "Requested to use GPU for bundle adjustment, but COLMAP was "
+           "compiled without CUDA support. Falling back to CPU-based "
+           "solvers.";
+  }
+#endif  // GLOMAP_CUDA_ENABLED
+
   // Do not use the iterative solver, as it does not seem to be helpful
   options_.solver_options.linear_solver_type = ceres::SPARSE_SCHUR;
   options_.solver_options.preconditioner_type = ceres::CLUSTER_TRIDIAGONAL;

glomap/estimators/bundle_adjustment.h

@@ -16,7 +16,7 @@ struct BundleAdjusterOptions : public OptimizationBaseOptions {
   bool optimize_intrinsics = true;
   bool optimize_points = true;
 
-  bool use_gpu = false;
+  bool use_gpu = true;
   std::string gpu_index = "-1";
   int min_num_images_gpu_solver = 300;
 

glomap/estimators/global_positioning.h

@@ -29,9 +29,9 @@ struct GlobalPositionerOptions : public OptimizationBaseOptions {
   bool optimize_points = true;
   bool optimize_scales = true;
 
-  bool use_gpu = false;
+  bool use_gpu = true;
   std::string gpu_index = "-1";
-  int min_num_images_gpu_solver = 2000;
+  int min_num_images_gpu_solver = 1000;
 
   // Constrain the minimum number of views per track
   int min_num_view_per_track = 3;

glomap/glomap_gpu.cc

@@ -13,9 +13,11 @@ int ShowHelp(
             << std::endl;
 
 #ifdef GLOMAP_CUDA_ENABLED
-    std::cout << "\nThis version was compiled with CUDA!\n" << std::endl;
+    std::cout << "This version was compiled with CUDA!" << std::endl
+              << std::endl;
 #else
-    std::cout << "\nThis version was NOT compiled CUDA!\n" << std::endl;
+    std::cout << "This version was NOT compiled CUDA!" << std::endl
+              << std::endl;
 #endif
 
   std::cout << "Usage:" << std::endl;