Modifications to C++ plots for interactive raytrace plots (#3776)

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Patrick Shriwise 2026-02-08 12:11:19 -06:00 committed by GitHub
parent 04bee9c49f
commit 6efc9db7b3
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2 changed files with 170 additions and 104 deletions

View file

@ -88,14 +88,21 @@ const RGBColor BLACK {0, 0, 0};
* is designed to be implemented by classes that produce plot-relevant data
* which can be visualized.
*/
typedef xt::xtensor<RGBColor, 2> ImageData;
class PlottableInterface {
public:
PlottableInterface() = default;
void set_default_colors();
private:
void set_id(pugi::xml_node plot_node);
int id_; // unique plot ID
void set_bg_color(pugi::xml_node plot_node);
void set_universe(pugi::xml_node plot_node);
void set_default_colors(pugi::xml_node plot_node);
void set_color_by(pugi::xml_node plot_node);
void set_user_colors(pugi::xml_node plot_node);
void set_overlap_color(pugi::xml_node plot_node);
void set_mask(pugi::xml_node plot_node);
@ -107,9 +114,15 @@ protected:
public:
enum class PlotColorBy { cells = 0, mats = 1 };
// Generates image data based on plot parameters and returns it
virtual ImageData create_image() const = 0;
// Creates the output image named path_plot_
virtual void create_output() const = 0;
// Write populated image data to file
void write_image(const ImageData& data) const;
// Print useful info to the terminal
virtual void print_info() const = 0;
@ -117,20 +130,19 @@ public:
std::string& path_plot() { return path_plot_; }
int id() const { return id_; }
int level() const { return level_; }
PlotColorBy color_by() const { return color_by_; }
// Public color-related data
PlottableInterface(pugi::xml_node plot_node);
virtual ~PlottableInterface() = default;
int level_; // Universe level to plot
bool color_overlaps_; // Show overlapping cells?
int level_ {-1}; // Universe level to plot
bool color_overlaps_ {false}; // Show overlapping cells?
PlotColorBy color_by_; // Plot coloring (cell/material)
RGBColor not_found_ {WHITE}; // Plot background color
RGBColor overlap_color_ {RED}; // Plot overlap color
vector<RGBColor> colors_; // Plot colors
};
typedef xt::xtensor<RGBColor, 2> ImageData;
struct IdData {
// Constructor
IdData(size_t h_res, size_t v_res);
@ -166,6 +178,11 @@ public:
enum class PlotBasis { xy = 1, xz = 2, yz = 3 };
// Accessors
const std::array<size_t, 3>& pixels() const { return pixels_; }
std::array<size_t, 3>& pixels() { return pixels_; }
// Members
public:
Position origin_; //!< Plot origin in geometry
@ -270,11 +287,11 @@ private:
public:
// Add mesh lines to ImageData
void draw_mesh_lines(ImageData& data) const;
void create_image() const;
ImageData create_image() const override;
void create_voxel() const;
virtual void create_output() const;
virtual void print_info() const;
void create_output() const override;
void print_info() const override;
PlotType type_; //!< Plot type (Slice/Voxel)
int meshlines_width_; //!< Width of lines added to the plot
@ -294,17 +311,32 @@ public:
*/
class RayTracePlot : public PlottableInterface {
public:
RayTracePlot() = default;
RayTracePlot(pugi::xml_node plot);
// Standard getters. No setting since it's done from XML.
const Position& camera_position() const { return camera_position_; }
Position& camera_position() { return camera_position_; }
const Position& look_at() const { return look_at_; }
Position& look_at() { return look_at_; }
const double& horizontal_field_of_view() const
{
return horizontal_field_of_view_;
}
double& horizontal_field_of_view() { return horizontal_field_of_view_; }
virtual void print_info() const;
void print_info() const override;
const std::array<int, 2>& pixels() const { return pixels_; }
std::array<int, 2>& pixels() { return pixels_; }
const Direction& up() const { return up_; }
Direction& up() { return up_; }
//! brief Updates the cached camera-to-model matrix after changes to
//! camera parameters.
void update_view();
protected:
Direction camera_x_axis() const
@ -330,8 +362,6 @@ protected:
*/
std::pair<Position, Direction> get_pixel_ray(int horiz, int vert) const;
std::array<int, 2> pixels_; // pixel dimension of resulting image
private:
void set_look_at(pugi::xml_node node);
void set_camera_position(pugi::xml_node node);
@ -341,8 +371,8 @@ private:
double horizontal_field_of_view_ {70.0}; // horiz. f.o.v. in degrees
Position camera_position_; // where camera is
Position look_at_; // point camera is centered looking at
Position look_at_; // point camera is centered looking at
std::array<int, 2> pixels_; // pixel dimension of resulting image
Direction up_ {0.0, 0.0, 1.0}; // which way is up
/* The horizontal thickness, if using an orthographic projection.
@ -377,8 +407,9 @@ class WireframeRayTracePlot : public RayTracePlot {
public:
WireframeRayTracePlot(pugi::xml_node plot);
virtual void create_output() const;
virtual void print_info() const;
ImageData create_image() const override;
void create_output() const override;
void print_info() const override;
private:
void set_opacities(pugi::xml_node node);
@ -434,10 +465,22 @@ class SolidRayTracePlot : public RayTracePlot {
friend class PhongRay;
public:
SolidRayTracePlot() = default;
SolidRayTracePlot(pugi::xml_node plot);
virtual void create_output() const;
virtual void print_info() const;
ImageData create_image() const override;
void create_output() const override;
void print_info() const override;
const std::unordered_set<int>& opaque_ids() const { return opaque_ids_; }
std::unordered_set<int>& opaque_ids() { return opaque_ids_; }
const Position& light_location() const { return light_location_; }
Position& light_location() { return light_location_; }
const double& diffuse_fraction() const { return diffuse_fraction_; }
double& diffuse_fraction() { return diffuse_fraction_; }
private:
void set_opaque_ids(pugi::xml_node node);
@ -496,7 +539,7 @@ public:
: Ray(r, u), plot_(plot), line_segments_(line_segments)
{}
virtual void on_intersection() override;
void on_intersection() override;
private:
/* Store a reference to the plot object which is running this ray, in order
@ -519,7 +562,7 @@ public:
result_color_ = plot_.not_found_;
}
virtual void on_intersection() override;
void on_intersection() override;
const RGBColor& result_color() { return result_color_; }

View file

@ -15,6 +15,7 @@
#include <png.h>
#endif
#include "openmc/cell.h"
#include "openmc/constants.h"
#include "openmc/container_util.h"
#include "openmc/dagmc.h"
@ -123,11 +124,21 @@ extern "C" int openmc_plot_geometry()
return 0;
}
void PlottableInterface::write_image(const ImageData& data) const
{
#ifdef USE_LIBPNG
output_png(path_plot(), data);
#else
output_ppm(path_plot(), data);
#endif
}
void Plot::create_output() const
{
if (PlotType::slice == type_) {
// create 2D image
create_image();
ImageData image = create_image();
write_image(image);
} else if (PlotType::voxel == type_) {
// create voxel file for 3D viewing
create_voxel();
@ -170,9 +181,9 @@ void Plot::print_info() const
fmt::print("Basis: YZ\n");
break;
}
fmt::print("Pixels: {} {}\n", pixels_[0], pixels_[1]);
fmt::print("Pixels: {} {}\n", pixels()[0], pixels()[1]);
} else if (PlotType::voxel == type_) {
fmt::print("Voxels: {} {} {}\n", pixels_[0], pixels_[1], pixels_[2]);
fmt::print("Voxels: {} {} {}\n", pixels()[0], pixels()[1], pixels()[2]);
}
}
@ -234,11 +245,10 @@ void free_memory_plot()
// creates an image based on user input from a plots.xml <plot>
// specification in the PNG/PPM format
void Plot::create_image() const
ImageData Plot::create_image() const
{
size_t width = pixels_[0];
size_t height = pixels_[1];
size_t width = pixels()[0];
size_t height = pixels()[1];
ImageData data({width, height}, not_found_);
@ -275,12 +285,7 @@ void Plot::create_image() const
draw_mesh_lines(data);
}
// create image file
#ifdef USE_LIBPNG
output_png(path_plot(), data);
#else
output_ppm(path_plot(), data);
#endif
return data;
}
void PlottableInterface::set_id(pugi::xml_node plot_node)
@ -348,17 +353,17 @@ void Plot::set_output_path(pugi::xml_node plot_node)
vector<int> pxls = get_node_array<int>(plot_node, "pixels");
if (PlotType::slice == type_) {
if (pxls.size() == 2) {
pixels_[0] = pxls[0];
pixels_[1] = pxls[1];
pixels()[0] = pxls[0];
pixels()[1] = pxls[1];
} else {
fatal_error(
fmt::format("<pixels> must be length 2 in slice plot {}", id()));
}
} else if (PlotType::voxel == type_) {
if (pxls.size() == 3) {
pixels_[0] = pxls[0];
pixels_[1] = pxls[1];
pixels_[2] = pxls[2];
pixels()[0] = pxls[0];
pixels()[1] = pxls[1];
pixels()[2] = pxls[2];
} else {
fatal_error(
fmt::format("<pixels> must be length 3 in voxel plot {}", id()));
@ -447,23 +452,31 @@ void PlottableInterface::set_universe(pugi::xml_node plot_node)
}
}
void PlottableInterface::set_default_colors(pugi::xml_node plot_node)
void PlottableInterface::set_color_by(pugi::xml_node plot_node)
{
// Copy plot color type and initialize all colors randomly
// Copy plot color type
std::string pl_color_by = "cell";
if (check_for_node(plot_node, "color_by")) {
pl_color_by = get_node_value(plot_node, "color_by", true);
}
if ("cell" == pl_color_by) {
color_by_ = PlotColorBy::cells;
colors_.resize(model::cells.size());
} else if ("material" == pl_color_by) {
color_by_ = PlotColorBy::mats;
colors_.resize(model::materials.size());
} else {
fatal_error(fmt::format(
"Unsupported plot color type '{}' in plot {}", pl_color_by, id()));
}
}
void PlottableInterface::set_default_colors()
{
// Copy plot color type and initialize all colors randomly
if (PlotColorBy::cells == color_by_) {
colors_.resize(model::cells.size());
} else if (PlotColorBy::mats == color_by_) {
colors_.resize(model::materials.size());
}
for (auto& c : colors_) {
c = random_color();
@ -710,7 +723,8 @@ PlottableInterface::PlottableInterface(pugi::xml_node plot_node)
set_id(plot_node);
set_bg_color(plot_node);
set_universe(plot_node);
set_default_colors(plot_node);
set_color_by(plot_node);
set_default_colors();
set_user_colors(plot_node);
set_mask(plot_node);
set_overlap_color(plot_node);
@ -857,27 +871,27 @@ void Plot::draw_mesh_lines(ImageData& data) const
int ax2_min, ax2_max;
if (axis_lines.second.size() > 0) {
double frac = (axis_lines.second.back() - ll_plot[ax2]) / width[ax2];
ax2_min = (1.0 - frac) * pixels_[1];
ax2_min = (1.0 - frac) * pixels()[1];
if (ax2_min < 0)
ax2_min = 0;
frac = (axis_lines.second.front() - ll_plot[ax2]) / width[ax2];
ax2_max = (1.0 - frac) * pixels_[1];
if (ax2_max > pixels_[1])
ax2_max = pixels_[1];
ax2_max = (1.0 - frac) * pixels()[1];
if (ax2_max > pixels()[1])
ax2_max = pixels()[1];
} else {
ax2_min = 0;
ax2_max = pixels_[1];
ax2_max = pixels()[1];
}
// Iterate across the first axis and draw lines.
for (auto ax1_val : axis_lines.first) {
double frac = (ax1_val - ll_plot[ax1]) / width[ax1];
int ax1_ind = frac * pixels_[0];
int ax1_ind = frac * pixels()[0];
for (int ax2_ind = ax2_min; ax2_ind < ax2_max; ++ax2_ind) {
for (int plus = 0; plus <= meshlines_width_; plus++) {
if (ax1_ind + plus >= 0 && ax1_ind + plus < pixels_[0])
if (ax1_ind + plus >= 0 && ax1_ind + plus < pixels()[0])
data(ax1_ind + plus, ax2_ind) = rgb;
if (ax1_ind - plus >= 0 && ax1_ind - plus < pixels_[0])
if (ax1_ind - plus >= 0 && ax1_ind - plus < pixels()[0])
data(ax1_ind - plus, ax2_ind) = rgb;
}
}
@ -887,27 +901,27 @@ void Plot::draw_mesh_lines(ImageData& data) const
int ax1_min, ax1_max;
if (axis_lines.first.size() > 0) {
double frac = (axis_lines.first.front() - ll_plot[ax1]) / width[ax1];
ax1_min = frac * pixels_[0];
ax1_min = frac * pixels()[0];
if (ax1_min < 0)
ax1_min = 0;
frac = (axis_lines.first.back() - ll_plot[ax1]) / width[ax1];
ax1_max = frac * pixels_[0];
if (ax1_max > pixels_[0])
ax1_max = pixels_[0];
ax1_max = frac * pixels()[0];
if (ax1_max > pixels()[0])
ax1_max = pixels()[0];
} else {
ax1_min = 0;
ax1_max = pixels_[0];
ax1_max = pixels()[0];
}
// Iterate across the second axis and draw lines.
for (auto ax2_val : axis_lines.second) {
double frac = (ax2_val - ll_plot[ax2]) / width[ax2];
int ax2_ind = (1.0 - frac) * pixels_[1];
int ax2_ind = (1.0 - frac) * pixels()[1];
for (int ax1_ind = ax1_min; ax1_ind < ax1_max; ++ax1_ind) {
for (int plus = 0; plus <= meshlines_width_; plus++) {
if (ax2_ind + plus >= 0 && ax2_ind + plus < pixels_[1])
if (ax2_ind + plus >= 0 && ax2_ind + plus < pixels()[1])
data(ax1_ind, ax2_ind + plus) = rgb;
if (ax2_ind - plus >= 0 && ax2_ind - plus < pixels_[1])
if (ax2_ind - plus >= 0 && ax2_ind - plus < pixels()[1])
data(ax1_ind, ax2_ind - plus) = rgb;
}
}
@ -928,9 +942,9 @@ void Plot::create_voxel() const
{
// compute voxel widths in each direction
array<double, 3> vox;
vox[0] = width_[0] / static_cast<double>(pixels_[0]);
vox[1] = width_[1] / static_cast<double>(pixels_[1]);
vox[2] = width_[2] / static_cast<double>(pixels_[2]);
vox[0] = width_[0] / static_cast<double>(pixels()[0]);
vox[1] = width_[1] / static_cast<double>(pixels()[1]);
vox[2] = width_[2] / static_cast<double>(pixels()[2]);
// initial particle position
Position ll = origin_ - width_ / 2.;
@ -952,18 +966,18 @@ void Plot::create_voxel() const
// Write current date and time
write_attribute(file_id, "date_and_time", time_stamp().c_str());
array<int, 3> pixels;
std::copy(pixels_.begin(), pixels_.end(), pixels.begin());
write_attribute(file_id, "num_voxels", pixels);
array<int, 3> h5_pixels;
std::copy(pixels().begin(), pixels().end(), h5_pixels.begin());
write_attribute(file_id, "num_voxels", h5_pixels);
write_attribute(file_id, "voxel_width", vox);
write_attribute(file_id, "lower_left", ll);
// Create dataset for voxel data -- note that the dimensions are reversed
// since we want the order in the file to be z, y, x
hsize_t dims[3];
dims[0] = pixels_[2];
dims[1] = pixels_[1];
dims[2] = pixels_[0];
dims[0] = pixels()[2];
dims[1] = pixels()[1];
dims[2] = pixels()[0];
hid_t dspace, dset, memspace;
voxel_init(file_id, &(dims[0]), &dspace, &dset, &memspace);
@ -971,11 +985,11 @@ void Plot::create_voxel() const
pltbase.width_ = width_;
pltbase.origin_ = origin_;
pltbase.basis_ = PlotBasis::xy;
pltbase.pixels_ = pixels_;
pltbase.pixels() = pixels();
pltbase.slice_color_overlaps_ = color_overlaps_;
ProgressBar pb;
for (int z = 0; z < pixels_[2]; z++) {
for (int z = 0; z < pixels()[2]; z++) {
// update z coordinate
pltbase.origin_.z = ll.z + z * vox[2];
@ -993,7 +1007,7 @@ void Plot::create_voxel() const
// update progress bar
pb.set_value(
100. * static_cast<double>(z + 1) / static_cast<double>((pixels_[2])));
100. * static_cast<double>(z + 1) / static_cast<double>((pixels()[2])));
}
voxel_finalize(dspace, dset, memspace);
@ -1052,7 +1066,10 @@ RayTracePlot::RayTracePlot(pugi::xml_node node) : PlottableInterface(node)
check_for_node(node, "field_of_view"))
fatal_error("orthographic_width and field_of_view are mutually exclusive "
"parameters.");
}
void RayTracePlot::update_view()
{
// Get centerline vector for camera-to-model. We create vectors around this
// that form a pixel array, and then trace rays along that.
auto up = up_ / up_.norm();
@ -1079,6 +1096,7 @@ WireframeRayTracePlot::WireframeRayTracePlot(pugi::xml_node node)
set_wireframe_thickness(node);
set_wireframe_ids(node);
set_wireframe_color(node);
update_view();
}
void WireframeRayTracePlot::set_wireframe_color(pugi::xml_node plot_node)
@ -1182,8 +1200,8 @@ std::pair<Position, Direction> RayTracePlot::get_pixel_ray(
// Compute field of view in radians
constexpr double DEGREE_TO_RADIAN = M_PI / 180.0;
double horiz_fov_radians = horizontal_field_of_view_ * DEGREE_TO_RADIAN;
double p0 = static_cast<double>(pixels_[0]);
double p1 = static_cast<double>(pixels_[1]);
double p0 = static_cast<double>(pixels()[0]);
double p1 = static_cast<double>(pixels()[1]);
double vert_fov_radians = horiz_fov_radians * p1 / p0;
// focal_plane_dist can be changed to alter the perspective distortion
@ -1219,10 +1237,10 @@ std::pair<Position, Direction> RayTracePlot::get_pixel_ray(
return result;
}
void WireframeRayTracePlot::create_output() const
ImageData WireframeRayTracePlot::create_image() const
{
size_t width = pixels_[0];
size_t height = pixels_[1];
size_t width = pixels()[0];
size_t height = pixels()[1];
ImageData data({width, height}, not_found_);
// This array marks where the initial wireframe was drawn. We convolve it with
@ -1245,11 +1263,11 @@ void WireframeRayTracePlot::create_output() const
std::vector<std::vector<std::vector<TrackSegment>>> this_line_segments(
n_threads);
for (int t = 0; t < n_threads; ++t) {
this_line_segments[t].resize(pixels_[0]);
this_line_segments[t].resize(pixels()[0]);
}
// The last thread writes to this, and the first thread reads from it.
std::vector<std::vector<TrackSegment>> old_segments(pixels_[0]);
std::vector<std::vector<TrackSegment>> old_segments(pixels()[0]);
#pragma omp parallel
{
@ -1257,7 +1275,7 @@ void WireframeRayTracePlot::create_output() const
const int tid = thread_num();
int vert = tid;
for (int iter = 0; iter <= pixels_[1] / n_threads; iter++) {
for (int iter = 0; iter <= pixels()[1] / n_threads; iter++) {
// Save bottom line of current work chunk to compare against later. This
// used to be inside the below if block, but it causes a spurious line to
@ -1266,9 +1284,9 @@ void WireframeRayTracePlot::create_output() const
if (tid == n_threads - 1)
old_segments = this_line_segments[n_threads - 1];
if (vert < pixels_[1]) {
if (vert < pixels()[1]) {
for (int horiz = 0; horiz < pixels_[0]; ++horiz) {
for (int horiz = 0; horiz < pixels()[0]; ++horiz) {
// RayTracePlot implements camera ray generation
std::pair<Position, Direction> ru = get_pixel_ray(horiz, vert);
@ -1330,7 +1348,7 @@ void WireframeRayTracePlot::create_output() const
// Now that the horizontal line has finished rendering, we can fill in
// wireframe entries that require comparison among all the threads. Hence
// the omp barrier being used. It has to be OUTSIDE any if blocks!
if (vert < pixels_[1]) {
if (vert < pixels()[1]) {
// Loop over horizontal pixels, checking intersection stack of upper
// neighbor
@ -1340,7 +1358,7 @@ void WireframeRayTracePlot::create_output() const
else
top_cmp = &this_line_segments[tid - 1];
for (int horiz = 0; horiz < pixels_[0]; ++horiz) {
for (int horiz = 0; horiz < pixels()[0]; ++horiz) {
if (!trackstack_equivalent(
this_line_segments[tid][horiz], (*top_cmp)[horiz])) {
wireframe_initial(horiz, vert) = 1;
@ -1357,8 +1375,8 @@ void WireframeRayTracePlot::create_output() const
} // end omp parallel
// Now thicken the wireframe lines and apply them to our image
for (int vert = 0; vert < pixels_[1]; ++vert) {
for (int horiz = 0; horiz < pixels_[0]; ++horiz) {
for (int vert = 0; vert < pixels()[1]; ++vert) {
for (int horiz = 0; horiz < pixels()[0]; ++horiz) {
if (wireframe_initial(horiz, vert)) {
if (wireframe_thickness_ == 1)
data(horiz, vert) = wireframe_color_;
@ -1369,19 +1387,21 @@ void WireframeRayTracePlot::create_output() const
if (i * i + j * j < wireframe_thickness_ * wireframe_thickness_) {
// Check if wireframe pixel is out of bounds
int w_i = std::max(std::min(horiz + i, pixels_[0] - 1), 0);
int w_j = std::max(std::min(vert + j, pixels_[1] - 1), 0);
int w_i = std::max(std::min(horiz + i, pixels()[0] - 1), 0);
int w_j = std::max(std::min(vert + j, pixels()[1] - 1), 0);
data(w_i, w_j) = wireframe_color_;
}
}
}
}
#ifdef USE_LIBPNG
output_png(path_plot(), data);
#else
output_ppm(path_plot(), data);
#endif
return data;
}
void WireframeRayTracePlot::create_output() const
{
ImageData data = create_image();
write_image(data);
}
void RayTracePlot::print_info() const
@ -1391,7 +1411,7 @@ void RayTracePlot::print_info() const
fmt::print("Look at: {} {} {}\n", look_at_.x, look_at_.y, look_at_.z);
fmt::print(
"Horizontal field of view: {} degrees\n", horizontal_field_of_view_);
fmt::print("Pixels: {} {}\n", pixels_[0], pixels_[1]);
fmt::print("Pixels: {} {}\n", pixels()[0], pixels()[1]);
}
void WireframeRayTracePlot::print_info() const
@ -1473,8 +1493,8 @@ void RayTracePlot::set_pixels(pugi::xml_node node)
if (pxls.size() != 2)
fatal_error(
fmt::format("<pixels> must be length 2 in projection plot {}", id()));
pixels_[0] = pxls[0];
pixels_[1] = pxls[1];
pixels()[0] = pxls[0];
pixels()[1] = pxls[1];
}
void RayTracePlot::set_camera_position(pugi::xml_node node)
@ -1521,6 +1541,7 @@ SolidRayTracePlot::SolidRayTracePlot(pugi::xml_node node) : RayTracePlot(node)
set_opaque_ids(node);
set_diffuse_fraction(node);
set_light_position(node);
update_view();
}
void SolidRayTracePlot::print_info() const
@ -1529,15 +1550,15 @@ void SolidRayTracePlot::print_info() const
RayTracePlot::print_info();
}
void SolidRayTracePlot::create_output() const
ImageData SolidRayTracePlot::create_image() const
{
size_t width = pixels_[0];
size_t height = pixels_[1];
size_t width = pixels()[0];
size_t height = pixels()[1];
ImageData data({width, height}, not_found_);
#pragma omp parallel for schedule(dynamic) collapse(2)
for (int horiz = 0; horiz < pixels_[0]; ++horiz) {
for (int vert = 0; vert < pixels_[1]; ++vert) {
for (int horiz = 0; horiz < pixels()[0]; ++horiz) {
for (int vert = 0; vert < pixels()[1]; ++vert) {
// RayTracePlot implements camera ray generation
std::pair<Position, Direction> ru = get_pixel_ray(horiz, vert);
PhongRay ray(ru.first, ru.second, *this);
@ -1546,11 +1567,13 @@ void SolidRayTracePlot::create_output() const
}
}
#ifdef USE_LIBPNG
output_png(path_plot(), data);
#else
output_ppm(path_plot(), data);
#endif
return data;
}
void SolidRayTracePlot::create_output() const
{
ImageData data = create_image();
write_image(data);
}
void SolidRayTracePlot::set_opaque_ids(pugi::xml_node node)