redstrate/raytracer
1
Fork 0
Code Activity

Reformat code

Browse source
This commit is contained in:
Joshua Goins 2022-08-16 07:41:12 -04:00
parent f0713452fc
commit 81d5045037
13 changed files with 370 additions and 319 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

33
.clang-format Normal file
View file

@ -0,0 +1,33 @@
---
AllowShortIfStatementsOnASingleLine: Never
CompactNamespaces: 'false'
DisableFormat: 'false'
IndentCaseLabels: 'true'
IndentPPDirectives: BeforeHash
IndentWidth: '4'
Language: Cpp
NamespaceIndentation: All
PointerAlignment: Left
ReflowComments: 'true'
SortIncludes: 'true'
SortUsingDeclarations: 'true'
SpacesInCStyleCastParentheses: 'false'
Standard: Cpp11
TabWidth: '0'
UseTab: Never
AllowShortEnumsOnASingleLine: false
BraceWrapping:
AfterEnum: true
AccessModifierOffset: -4
SpaceAfterTemplateKeyword: 'false'
AllowAllParametersOfDeclarationOnNextLine: false
AlignAfterOpenBracket: AlwaysBreak
BinPackArguments: false
BinPackParameters: false
ColumnLimit: 120
AllowShortBlocksOnASingleLine: 'false'
AllowShortCaseLabelsOnASingleLine: 'false'
AllowShortFunctionsOnASingleLine: 'Empty'
AllowShortLambdasOnASingleLine: 'Empty'
AllowShortLoopsOnASingleLine: 'false'
SeparateDefinitionBlocks : 'Always'

8
.editorconfig Normal file
View file

@ -0,0 +1,8 @@
root = true
[*]
insert_final_newline = true
indent_style = space
indent_size = 4
tab_width = 4
max_line_length = 120

30
CMakeLists.txt
View file

@ -9,21 +9,21 @@ find_package(SDL2 REQUIRED)
add_subdirectory(extern)
add_executable(raytracer
include/camera.h
include/intersections.h
include/lighting.h
include/ray.h
include/image.h
include/tiny_obj_loader.h
include/scene.h
include/aabb.h
include/octree.h
src/main.cpp
src/scene.cpp)
include/camera.h
include/intersections.h
include/lighting.h
include/ray.h
include/image.h
include/tiny_obj_loader.h
include/scene.h
include/aabb.h
include/octree.h
src/main.cpp
src/scene.cpp)
target_include_directories(raytracer PUBLIC include PRIVATE ${GLM_INCLUDE_DIR})
target_link_libraries(raytracer PUBLIC stb SDL2::Main imgui glad)
set_target_properties(raytracer PROPERTIES
CXX_STANDARD 17
CXX_STANDARD_REQUIRED YES
CXX_EXTENSIONS NO
)
CXX_STANDARD 17
CXX_STANDARD_REQUIRED YES
CXX_EXTENSIONS NO
)

4
README.md
View file

@ -1,6 +1,8 @@
# Raytracer
A multi-threaded raytracer using glm, tinyobjloader and C++17. The UI is written in imgui and image display is
rendered using OpenGL. I tried to write this to not be insanely fast or compact like other raytracers, but to be readable and understandable.
rendered using OpenGL. I tried to write this to not be insanely fast or compact like other raytracers, but to be
readable and understandable.
![example result](misc/output.png)

33
include/aabb.h
View file

@ -2,28 +2,25 @@
struct AABB {
glm::vec3 min, max;
glm::vec3 center() const {
return 0.5f * (max + min);
}
glm::vec3 extent() const {
return max - center();
}
bool contains(const glm::vec3 point) const {
return glm::all(glm::lessThan(point, max)) && glm::all(glm::greaterThan(point, min));
}
bool inside(const AABB extent) const {
return(max.x > extent.min.x &&
min.x < extent.max.x &&
max.y > extent.min.y &&
min.y < extent.max.y &&
max.z > extent.min.z &&
min.z < extent.max.z);
return (
max.x > extent.min.x && min.x < extent.max.x && max.y > extent.min.y && min.y < extent.max.y &&
max.z > extent.min.z && min.z < extent.max.z);
}
bool contains(const Ray& ray) const {
const float t1 = (min.x - ray.origin.x) / ray.direction.x;
const float t2 = (max.x - ray.origin.x) / ray.direction.x;
@ -31,19 +28,19 @@ struct AABB {
const float t4 = (max.y - ray.origin.y) / ray.direction.y;
const float t5 = (min.z - ray.origin.z) / ray.direction.z;
const float t6 = (max.z - ray.origin.z) / ray.direction.z;
const float tmin = std::min(std::max(std::min(t1, t2), std::min(t3, t4)), std::min(t5, t6));
const float tmax = std::min(std::min(std::max(t1, t2), std::max(t3, t4)), std::max(t5, t6));
// if tmax < 0, ray (line) is intersecting AABB, but whole AABB is behing us
//if(tmax < 0)
// if(tmax < 0)
// return false;
// if tmin > tmax, ray doesn't intersect AABB
if(tmin > tmax)
if (tmin > tmax)
return false;
if(tmin < 0.0f)
if (tmin < 0.0f)
return true;
return true;

14
include/camera.h
View file

@ -5,24 +5,26 @@
class Camera {
public:
Camera() : position(glm::vec3(0)), direction(glm::vec3(0)) {}
Camera(glm::vec3 position, glm::vec3 direction) : position(position), direction(direction) {}
void look_at(glm::vec3 eye, glm::vec3 target) {
position = eye;
direction = glm::normalize(target - eye);
}
Ray get_ray(const int32_t x, const int32_t y, const int32_t width, const int32_t height) const {
const glm::vec3 up = glm::vec3(0, 1, 0);
const glm::vec3 right = glm::normalize(glm::cross(direction, up));
const float h2 = height / 2.0f;
const float w2 = width / 2.0f;
const glm::vec3 ray_dir = position + (h2 / tan(glm::radians(fov) / 2)) * direction + (y - h2) * up + static_cast<float>(x - w2) * right;
const glm::vec3 ray_dir = position + (h2 / tan(glm::radians(fov) / 2)) * direction + (y - h2) * up +
static_cast<float>(x - w2) * right;
return Ray(position, ray_dir);
}
glm::vec3 position, direction;
float fov = 45.0f;
};

13
include/image.h
View file

@ -1,22 +1,21 @@
#pragma once
#include <glm/glm.hpp>
#include <array>
#include <glm/glm.hpp>
template<class T, int Width, int Height>
class Image {
template<class T, int Width, int Height> class Image {
public:
void reset() {
array = {};
}
T& get(const int32_t x, const int32_t y) {
return array[y * Width + x];
}
T get(const int32_t x, const int32_t y) const {
return array[y * Width + x];
}
std::array<T, Width * Height> array = {};
std::array<T, Width* Height> array = {};
};

54
include/intersections.h
View file

@ -12,53 +12,57 @@ namespace intersections {
const float b = glm::dot(ray.direction, diff);
const float c = glm::dot(diff, diff) - sphere.w * sphere.w;
float t = b * b - c;
if (t > 0.0) {
t = -b - glm::sqrt(t);
if (t > 0.0)
return true;
}
return false;
}
inline float ray_triangle(const Ray ray,
const glm::vec3 v0,
const glm::vec3 v1,
const glm::vec3 v2,
float& t,
float& u,
float& v) {
inline float ray_triangle(
const Ray ray,
const glm::vec3 v0,
const glm::vec3 v1,
const glm::vec3 v2,
float& t,
float& u,
float& v) {
glm::vec3 e1 = v1 - v0;
glm::vec3 e2 = v2 - v0;
glm::vec3 pvec = glm::cross(ray.direction, e2);
float det = glm::dot(e1, pvec);
// if determinant is zero then ray is
// parallel with the triangle plane
if (det > -epsilon && det < epsilon) return false;
float invdet = 1.0/det;
if (det > -epsilon && det < epsilon)
return false;
float invdet = 1.0 / det;
// calculate distance from m[0] to origin
glm::vec3 tvec = ray.origin - v0;
// u and v are the barycentric coordinates
// in triangle if u >= 0, v >= 0 and u + v <= 1
u = glm::dot(tvec, pvec) * invdet;
// check against one edge and opposite point
if (u < 0.0 || u > 1.0) return false;
if (u < 0.0 || u > 1.0)
return false;
glm::vec3 qvec = glm::cross(tvec, e1);
v = glm::dot(ray.direction, qvec) * invdet;
// check against other edges
if (v < 0.0 || u + v > 1.0) return false;
//distance along the ray, i.e. intersect at o + t * d
if (v < 0.0 || u + v > 1.0)
return false;
// distance along the ray, i.e. intersect at o + t * d
t = glm::dot(e2, qvec) * invdet;
return true;
}
};
}; // namespace intersections

4
include/lighting.h
View file

@ -6,7 +6,7 @@ namespace lighting {
inline float point_light(const glm::vec3 pos, const glm::vec3 light, const glm::vec3 normal) {
const glm::vec3 dir = glm::normalize(light - pos);
const float n_dot_l = glm::max(glm::dot(normal, dir), 0.0f);
return n_dot_l;
}
};
}; // namespace lighting

52
include/octree.h
View file

@ -18,73 +18,71 @@ constexpr auto child_pattern = {
glm::vec3(-1, +1, +1),
};
template<typename UnderlyingType>
struct Node {
template<typename UnderlyingType> struct Node {
using NodeType = Node<UnderlyingType>;
AABB extent;
int depth = 0;
std::vector<UnderlyingType> contained_objects;
std::array<std::unique_ptr<NodeType>, 8> children;
bool is_split = false;
void add(UnderlyingType& object, const AABB extent) {
if(is_split) {
for(auto& child : children) {
if(extent.inside(child->extent))
if (is_split) {
for (auto& child : children) {
if (extent.inside(child->extent))
child->add(object, extent);
}
} else {
contained_objects.push_back(object);
if(contained_objects.size() >= max_contained_types && depth < max_octree_depth)
if (contained_objects.size() >= max_contained_types && depth < max_octree_depth)
split();
}
}
void split() {
is_split = true;
const auto center = extent.center();
const auto split_size = extent.extent().x / 2.0f;
int i = 0;
for(auto& point : child_pattern) {
for (auto& point : child_pattern) {
auto child = std::make_unique<NodeType>();
child->depth = depth + 1;
const auto position = center + point * split_size;
child->extent.min = glm::vec3(position.x - split_size, position.y - split_size, position.z - split_size);
child->extent.max = glm::vec3(position.x + split_size, position.y + split_size, position.z + split_size);
children[i++] = std::move(child);
}
for(auto& object : contained_objects) {
for(auto& child : children) {
if(object.extent.inside(child->extent))
for (auto& object : contained_objects) {
for (auto& child : children) {
if (object.extent.inside(child->extent))
child->add(object, extent);
}
}
contained_objects.clear();
}
};
template<typename UnderlyingType>
struct Octree {
template<typename UnderlyingType> struct Octree {
using NodeType = Node<UnderlyingType>;
NodeType root;
Octree(const glm::vec3 min, const glm::vec3 max) {
root = NodeType();
root.extent.min = min;
root.extent.max = max;
}
void add(UnderlyingType& object, const AABB extent) {
root.add(object, extent);
}

43
include/scene.h
View file

@ -1,17 +1,17 @@
#pragma once
#include <optional>
#include <glm/glm.hpp>
#include <array>
#include <glm/glm.hpp>
#include <iostream>
#include <optional>
#include <random>
#include <tiny_obj_loader.h>
#include "ray.h"
#include "intersections.h"
#include "lighting.h"
#include "octree.h"
#include "ray.h"
constexpr glm::vec3 light_position = glm::vec3(5);
constexpr float light_bias = 0.01f;
@ -32,34 +32,34 @@ glm::vec3 fetch_normal(const Object& object, const tinyobj::mesh_t& mesh, const
struct Object {
glm::vec3 position = glm::vec3(0);
glm::vec3 color = glm::vec3(1);
tinyobj::attrib_t attrib;
std::vector<tinyobj::shape_t> shapes;
std::vector<tinyobj::material_t> materials;
std::unique_ptr<Octree<TriangleBox>> octree;
void create_octree() {
octree = std::make_unique<Octree<TriangleBox>>(glm::vec3(-2), glm::vec3(2));
for(auto& shape : shapes) {
for(size_t i = 0; i < shape.mesh.num_face_vertices.size(); i++) {
for (auto& shape : shapes) {
for (size_t i = 0; i < shape.mesh.num_face_vertices.size(); i++) {
const glm::vec3 v0 = fetch_position(*this, shape.mesh, i, 0);
const glm::vec3 v1 = fetch_position(*this, shape.mesh, i, 1);
const glm::vec3 v2 = fetch_position(*this, shape.mesh, i, 2);
AABB extent;
extent.min = glm::min(v0, v1);
extent.min = glm::min(extent.min, v2);
extent.max = glm::max(v0, v1);
extent.max = glm::max(extent.max, v2);
TriangleBox box = {};
box.vertice_index = i;
box.extent = extent;
box.mesh = &shape.mesh;
octree->add(box, box.extent);
}
}
@ -68,29 +68,29 @@ struct Object {
struct Scene {
std::vector<std::unique_ptr<Object>> objects;
std::random_device rd;
std::mt19937 gen;
std::uniform_real_distribution<> dis;
Scene() : gen(rd()), dis(0.0, 1.0) {}
float distribution() {
return dis(gen);
}
Object& load_from_file(const std::string_view path) {
auto o = std::make_unique<Object>();
std::string err;
if(!tinyobj::LoadObj(&o->attrib, &o->shapes, &o->materials, &err, path.data()))
std::cerr << "Could not load obj: " << err;
if (!tinyobj::LoadObj(&o->attrib, &o->shapes, &o->materials, &err, path.data()))
std::cerr << "Could not load obj: " << err;
return *objects.emplace_back(std::move(o));
}
void generate_acceleration() {
for(auto& object : objects) {
for (auto& object : objects) {
object->create_octree();
}
}
@ -111,4 +111,3 @@ struct SceneResult {
};
std::optional<SceneResult> cast_scene(const Ray ray, Scene& scene, const bool use_bvh, const int depth = 0);

249
src/main.cpp
View file

@ -1,23 +1,23 @@
#include <iostream>
#include <limits>
#include <future>
#include <vector>
#include <glm/glm.hpp>
#include <SDL.h>
#include <array>
#include <future>
#include <glm/glm.hpp>
#include <iostream>
#include <limits>
#include <vector>
#define STB_IMAGE_WRITE_IMPLEMENTATION
#include <stb_image_write.h>
#include "intersections.h"
#include "camera.h"
#include "glad/glad.h"
#include "image.h"
#include "imgui.h"
#include "imgui_impl_opengl3.h"
#include "imgui_impl_sdl.h"
#include "intersections.h"
#include "lighting.h"
#include "scene.h"
#include "glad/glad.h"
#include "imgui.h"
#include "imgui_impl_sdl.h"
#include "imgui_impl_opengl3.h"
#define TINYOBJLOADER_IMPLEMENTATION
#include <tiny_obj_loader.h>
@ -29,7 +29,7 @@ bool use_bvh = true;
const Camera camera = [] {
Camera camera;
camera.look_at(glm::vec3(0, 0, 3), glm::vec3(0));
return camera;
}();
@ -50,23 +50,18 @@ enum class DisplayMode {
Reflect
};
const std::array diplay_mode_strings = {
"Combined",
"Direct",
"Indirect",
"Reflect"
};
const std::array diplay_mode_strings = {"Combined", "Direct", "Indirect", "Reflect"};
inline DisplayMode display_mode;
bool calculate_tile(const int32_t from_x, const int32_t to_width, const int32_t from_y, const int32_t to_height) {
for(int32_t y = from_y; y < (from_y + to_height); y++) {
for(int32_t x = from_x; x < (from_x + to_width); x++) {
for (int32_t y = from_y; y < (from_y + to_height); y++) {
for (int32_t x = from_x; x < (from_x + to_width); x++) {
Ray ray_camera = camera.get_ray(x, y, width, height);
if(auto result = cast_scene(ray_camera, scene, use_bvh)) {
if (auto result = cast_scene(ray_camera, scene, use_bvh)) {
glm::vec3 chosen_display;
switch(display_mode) {
switch (display_mode) {
case DisplayMode::Combined:
chosen_display = result->combined;
break;
@ -80,14 +75,14 @@ bool calculate_tile(const int32_t from_x, const int32_t to_width, const int32_t
chosen_display = result->reflect;
break;
}
colors.get(x, y) = glm::vec4(chosen_display, 1.0f);
image_dirty = true;
}
}
}
return true;
}
@ -98,76 +93,70 @@ GLuint pixels_texture = 0;
void setup_gfx() {
// create quad for pixel rendering
constexpr std::array vertices = {
-0.5f, 0.5f, 0.0f, 0.0f, 0.0f,
0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
0.5f, -0.5f, 0.0f, 1.0f, -1.0f,
-0.5f, -0.5f, 0.0f, 0.0f, -1.0f // we render it upside down (to opengl) so we flip our tex coord
-0.5f, 0.5f, 0.0f, 0.0f, 0.0f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.5f,
-0.5f, 0.0f, 1.0f, -1.0f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f // we render it upside down (to opengl) so we flip our
// tex coord
};
constexpr std::array elements = {
0, 1, 2,
2, 3, 0
};
constexpr std::array elements = {0, 1, 2, 2, 3, 0};
glGenVertexArrays(1, &quad_vao);
glBindVertexArray(quad_vao);
GLuint vbo = 0;
glGenBuffers(1, &vbo);
glBindBuffer(GL_ARRAY_BUFFER, vbo);
glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(float), vertices.data(), GL_STATIC_DRAW);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), nullptr);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), reinterpret_cast<void*>(3 * sizeof(float)));
glEnableVertexAttribArray(0);
glEnableVertexAttribArray(1);
GLuint ebo = 0;
glGenBuffers(1, &ebo);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, elements.size() * sizeof(uint32_t), elements.data(), GL_STATIC_DRAW);
constexpr std::string_view vertex_glsl =
"#version 330 core\n"
"layout (location = 0) in vec3 in_position;\n"
"layout (location = 1) in vec2 in_uv;\n"
"out vec2 uv;\n"
"void main()\n"
"{\n"
" gl_Position = vec4(in_position.xyz, 1.0);\n"
" uv = in_uv;\n"
"}\n";
constexpr std::string_view vertex_glsl = "#version 330 core\n"
"layout (location = 0) in vec3 in_position;\n"
"layout (location = 1) in vec2 in_uv;\n"
"out vec2 uv;\n"
"void main()\n"
"{\n"
" gl_Position = vec4(in_position.xyz, 1.0);\n"
" uv = in_uv;\n"
"}\n";
const char* vertex_src = vertex_glsl.data();
constexpr std::string_view fragment_glsl =
"#version 330 core\n"
"in vec2 uv;\n"
"out vec4 out_color;\n"
"uniform sampler2D pixel_texture;\n"
"void main()\n"
"{\n"
" out_color = texture(pixel_texture, uv);\n"
"}\n";
constexpr std::string_view fragment_glsl = "#version 330 core\n"
"in vec2 uv;\n"
"out vec4 out_color;\n"
"uniform sampler2D pixel_texture;\n"
"void main()\n"
"{\n"
" out_color = texture(pixel_texture, uv);\n"
"}\n";
const char* fragment_src = fragment_glsl.data();
GLuint vertex_shader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertex_shader, 1, &vertex_src, nullptr);
glCompileShader(vertex_shader);
GLuint fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragment_shader, 1, &fragment_src, nullptr);
glCompileShader(fragment_shader);
pixel_program = glCreateProgram();
glAttachShader(pixel_program, vertex_shader);
glAttachShader(pixel_program, fragment_shader);
glLinkProgram(pixel_program);
glDeleteShader(vertex_shader);
glDeleteShader(fragment_shader);
glGenTextures(1, &pixels_texture);
glBindTexture(GL_TEXTURE_2D, pixels_texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
@ -187,9 +176,9 @@ std::vector<std::future<bool>> futures;
void render() {
futures.clear();
colors.reset();
for(int32_t y = 0; y < num_tiles_y; y++) {
for(int32_t x = 0; x < num_tiles_x; x++) {
for (int32_t y = 0; y < num_tiles_y; y++) {
for (int32_t x = 0; x < num_tiles_x; x++) {
auto f = std::async(std::launch::async, calculate_tile, x * tile_size, tile_size, y * tile_size, tile_size);
futures.push_back(std::move(f));
}
@ -198,10 +187,10 @@ void render() {
void dump_to_file() {
uint8_t pixels[width * height * 3] = {};
int i = 0;
for(int32_t y = height - 1; y >= 0; y--) {
for(int32_t x = 0; x < width; x++) {
for (int32_t y = height - 1; y >= 0; y--) {
for (int32_t x = 0; x < width; x++) {
const glm::ivec4 c = colors.get(x, y);
pixels[i++] = c.r;
pixels[i++] = c.g;
@ -212,17 +201,24 @@ void dump_to_file() {
stbi_write_png("output.png", width, height, 3, pixels, width * 3);
}
template<typename UnderlyingType>
void walk_node(Node<UnderlyingType>& node) {
if(ImGui::TreeNode(&node, "min: (%f %f %f)\n max: (%f %f %f)", node.extent.min.x, node.extent.min.y, node.extent.min.z, node.extent.max.x, node.extent.max.y, node.extent.max.z)) {
template<typename UnderlyingType> void walk_node(Node<UnderlyingType>& node) {
if (ImGui::TreeNode(
&node,
"min: (%f %f %f)\n max: (%f %f %f)",
node.extent.min.x,
node.extent.min.y,
node.extent.min.z,
node.extent.max.x,
node.extent.max.y,
node.extent.max.z)) {
ImGui::Text("Is split: %i", node.is_split);
ImGui::Text("Contained triangles: %lu", node.contained_objects.size());
if(node.is_split) {
for(auto& child : node.children)
if (node.is_split) {
for (auto& child : node.children)
walk_node(*child);
}
ImGui::TreePop();
}
}
@ -233,104 +229,105 @@ void walk_object(Object& object) {
int main(int, char*[]) {
SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_FORWARD_COMPATIBLE_FLAG);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
SDL_Window* window = SDL_CreateWindow("raytracer",
SDL_WINDOWPOS_CENTERED,
SDL_WINDOWPOS_CENTERED,
800,
600,
SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
SDL_Window* window = SDL_CreateWindow(
"raytracer",
SDL_WINDOWPOS_CENTERED,
SDL_WINDOWPOS_CENTERED,
800,
600,
SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
SDL_GLContext gl_context = SDL_GL_CreateContext(window);
SDL_GL_MakeCurrent(window, gl_context);
SDL_GL_SetSwapInterval(1);
gladLoadGL();
setup_gfx();
ImGui::CreateContext();
ImGui::StyleColorsDark();
ImGui_ImplSDL2_InitForOpenGL(window, gl_context);
ImGui_ImplOpenGL3_Init("#version 330 core");
bool running = true;
while(running) {
while (running) {
SDL_Event event = {};
while(SDL_PollEvent(&event)) {
while (SDL_PollEvent(&event)) {
ImGui_ImplSDL2_ProcessEvent(&event);
if(event.type == SDL_QUIT)
if (event.type == SDL_QUIT)
running = false;
}
ImGui_ImplOpenGL3_NewFrame();
ImGui_ImplSDL2_NewFrame(window);
ImGui::NewFrame();
if(ImGui::BeginMainMenuBar()) {
if(ImGui::BeginMenu("File")) {
if(ImGui::Button("Load Example Models")) {
if (ImGui::BeginMainMenuBar()) {
if (ImGui::BeginMenu("File")) {
if (ImGui::Button("Load Example Models")) {
auto& sphere = scene.load_from_file("misc/sphere.obj");
sphere.color = {1, 1, 1};
auto& plane = scene.load_from_file("misc/plane.obj");
plane.position.y = -1;
plane.color = {1, 0, 0};
scene.generate_acceleration();
}
ImGui::EndMenu();
}
ImGui::EndMainMenuBar();
}
ImGui::Begin("Render Options");
ImGui::Checkbox("Use BVH", &use_bvh);
ImGui::InputInt("Indirect Samples", &num_indirect_samples);
if(ImGui::BeginCombo("Channel Selection", diplay_mode_strings[static_cast<int>(display_mode)])) {
if(ImGui::Selectable("Combined"))
if (ImGui::BeginCombo("Channel Selection", diplay_mode_strings[static_cast<int>(display_mode)])) {
if (ImGui::Selectable("Combined"))
display_mode = DisplayMode::Combined;
if(ImGui::Selectable("Direct"))
if (ImGui::Selectable("Direct"))
display_mode = DisplayMode::Direct;
if(ImGui::Selectable("Indirect"))
if (ImGui::Selectable("Indirect"))
display_mode = DisplayMode::Indirect;
if(ImGui::Selectable("Reflect"))
if (ImGui::Selectable("Reflect"))
display_mode = DisplayMode::Reflect;
ImGui::EndCombo();
}
if(ImGui::Button("Render"))
if (ImGui::Button("Render"))
render();
ImGui::SameLine();
if(ImGui::Button("Save Output"))
if (ImGui::Button("Save Output"))
dump_to_file();
if(image_dirty) {
if (image_dirty) {
update_texture();
image_dirty = false;
}
for(auto& object : scene.objects) {
if(ImGui::TreeNode("Object")) {
for (auto& object : scene.objects) {
if (ImGui::TreeNode("Object")) {
walk_object(*object);
ImGui::TreePop();
}
}
@ -338,18 +335,18 @@ int main(int, char*[]) {
ImGui::End();
ImGui::Render();
auto& io = ImGui::GetIO();
glViewport(0, 0, (int)io.DisplaySize.x, (int)io.DisplaySize.y);
glClear(GL_COLOR_BUFFER_BIT);
glUseProgram(pixel_program);
glBindVertexArray(quad_vao);
glBindTexture(GL_TEXTURE_2D, pixels_texture);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
SDL_GL_SwapWindow(window);
}

152
src/scene.cpp
View file

@ -1,48 +1,55 @@
#include "scene.h"
#include <glm/gtx/perpendicular.hpp>
#include <functional>
#include <glm/gtx/perpendicular.hpp>
constexpr double pi = 3.14159265358979323846l;
glm::vec3 fetch_position(const Object& object, const tinyobj::mesh_t& mesh, const int32_t index, const int32_t vertex) {
const tinyobj::index_t idx = mesh.indices[(index * 3) + vertex];
const auto vx = object.attrib.vertices[3 * idx.vertex_index];
const auto vy = object.attrib.vertices[3 * idx.vertex_index + 1];
const auto vz = object.attrib.vertices[3 * idx.vertex_index + 2];
return glm::vec3(vx, vy, vz);
}
glm::vec3 fetch_normal(const Object& object, const tinyobj::mesh_t& mesh, const int32_t index, const int32_t vertex) {
const tinyobj::index_t idx = mesh.indices[(index * 3) + vertex];
const auto nx = object.attrib.normals[3 * idx.normal_index];
const auto ny = object.attrib.normals[3 * idx.normal_index + 1];
const auto nz = object.attrib.normals[3 * idx.normal_index + 2];
return glm::vec3(nx, ny, nz);
}
bool test_triangle(const Ray ray, const Object& object, const tinyobj::mesh_t& mesh, const size_t i, float& tClosest, bool& intersection, HitResult& result) {
bool test_triangle(
const Ray ray,
const Object& object,
const tinyobj::mesh_t& mesh,
const size_t i,
float& tClosest,
bool& intersection,
HitResult& result) {
const glm::vec3 v0 = fetch_position(object, mesh, i, 0) + object.position;
const glm::vec3 v1 = fetch_position(object, mesh, i, 1) + object.position;
const glm::vec3 v2 = fetch_position(object, mesh, i, 2) + object.position;
float t = std::numeric_limits<float>::infinity(), u, v;
if(intersections::ray_triangle(ray, v0, v1, v2, t, u, v)) {
if(t < tClosest && t > epsilon) {
if (intersections::ray_triangle(ray, v0, v1, v2, t, u, v)) {
if (t < tClosest && t > epsilon) {
const glm::vec3 n0 = fetch_normal(object, mesh, i, 0);
const glm::vec3 n1 = fetch_normal(object, mesh, i, 1);
const glm::vec3 n2 = fetch_normal(object, mesh, i, 2);
result.normal = (1 - u - v) * n0 + u * n1 + v * n2;
result.position = ray.origin + ray.direction * t;
tClosest = t;
intersection = true;
return true;
}
}
@ -51,30 +58,30 @@ bool test_triangle(const Ray ray, const Object& object, const tinyobj::mesh_t& m
std::optional<HitResult> test_mesh(const Ray ray, const Object& object, const tinyobj::mesh_t& mesh, float& tClosest) {
bool intersection = false;
HitResult result = {};
for(size_t i = 0; i < mesh.num_face_vertices.size(); i++) {
for (size_t i = 0; i < mesh.num_face_vertices.size(); i++) {
const glm::vec3 v0 = fetch_position(object, mesh, i, 0) + object.position;
const glm::vec3 v1 = fetch_position(object, mesh, i, 1) + object.position;
const glm::vec3 v2 = fetch_position(object, mesh, i, 2) + object.position;
float t = std::numeric_limits<float>::infinity(), u, v;
if(intersections::ray_triangle(ray, v0, v1, v2, t, u, v)) {
if(t < tClosest && t > epsilon) {
if (intersections::ray_triangle(ray, v0, v1, v2, t, u, v)) {
if (t < tClosest && t > epsilon) {
const glm::vec3 n0 = fetch_normal(object, mesh, i, 0);
const glm::vec3 n1 = fetch_normal(object, mesh, i, 1);
const glm::vec3 n2 = fetch_normal(object, mesh, i, 2);
result.normal = (1 - u - v) * n0 + u * n1 + v * n2;
result.position = ray.origin + ray.direction * t;
tClosest = t;
intersection = true;
}
}
}
if(intersection)
if (intersection)
return result;
else
return {};
@ -84,30 +91,29 @@ std::optional<HitResult> test_scene(const Ray ray, const Scene& scene) {
bool intersection = false;
HitResult result = {};
float tClosest = std::numeric_limits<float>::infinity();
for(auto& object : scene.objects) {
for(uint32_t i = 0; i < object->shapes.size(); i++) {
for (auto& object : scene.objects) {
for (uint32_t i = 0; i < object->shapes.size(); i++) {
auto mesh = object->shapes[i].mesh;
if(const auto hit = test_mesh(ray, *object, mesh, tClosest)) {
if (const auto hit = test_mesh(ray, *object, mesh, tClosest)) {
intersection = true;
result = hit.value();
result.object = object.get();
}
}
}
if(intersection)
if (intersection)
return result;
else
return {};
}
template<typename T>
Node<T>* find_hit_ray_search(Node<T>& node, const Ray ray, std::vector<Node<T>*>* out) {
if(node.extent.contains(ray)) {
if(node.is_split) {
for(auto& child : node.children)
template<typename T> Node<T>* find_hit_ray_search(Node<T>& node, const Ray ray, std::vector<Node<T>*>* out) {
if (node.extent.contains(ray)) {
if (node.is_split) {
for (auto& child : node.children)
find_hit_ray_search(*child, ray, out);
} else {
out->push_back(&node);
@ -117,12 +123,11 @@ Node<T>* find_hit_ray_search(Node<T>& node, const Ray ray, std::vector<Node<T>*>
return nullptr;
}
template<typename T>
std::vector<Node<T>*> find_hit_ray(Node<T>& node, const Ray ray) {
template<typename T> std::vector<Node<T>*> find_hit_ray(Node<T>& node, const Ray ray) {
std::vector<Node<T>*> vec;
find_hit_ray_search(node, ray, &vec);
return vec;
}
@ -130,17 +135,24 @@ std::optional<HitResult> test_scene_octree(const Ray ray, const Scene& scene) {
bool intersection = false;
HitResult result = {};
float tClosest = std::numeric_limits<float>::infinity();
for(auto& object : scene.objects) {
for(auto& node : find_hit_ray(object->octree->root, ray)) {
for(auto& triangle_object : node->contained_objects) {
if(test_triangle(ray, *object, *triangle_object.mesh, triangle_object.vertice_index, tClosest, intersection, result))
for (auto& object : scene.objects) {
for (auto& node : find_hit_ray(object->octree->root, ray)) {
for (auto& triangle_object : node->contained_objects) {
if (test_triangle(
ray,
*object,
*triangle_object.mesh,
triangle_object.vertice_index,
tClosest,
intersection,
result))
result.object = object.get();
}
}
}
if(intersection)
if (intersection)
return result;
else
return {};
@ -149,7 +161,7 @@ std::optional<HitResult> test_scene_octree(const Ray ray, const Scene& scene) {
// methods adapated from https://users.cg.tuwien.ac.at/zsolnai/gfx/smallpaint/
std::tuple<glm::vec3, glm::vec3> orthogonal_system(const glm::vec3& v1) {
glm::vec3 v2;
if(glm::abs(v1.x) > glm::abs(v1.y)) {
if (glm::abs(v1.x) > glm::abs(v1.y)) {
// project to the y = 0 plane and construct a normalized orthogonal vector in this plane
const float inverse_length = 1.0f / sqrtf(v1.x * v1.x + v1.z * v1.z);
v2 = glm::vec3(-v1.z * inverse_length, 0.0f, v1.x * inverse_length);
@ -158,14 +170,14 @@ std::tuple<glm::vec3, glm::vec3> orthogonal_system(const glm::vec3& v1) {
const float inverse_length = 1.0f / sqrtf(v1.y * v1.y + v1.z * v1.z);
v2 = glm::vec3(0.0f, v1.z * inverse_length, -v1.y * inverse_length);
}
return {v2, glm::cross(v1, v2)};
}
glm::vec3 hemisphere(const double u1, const double u2) {
const double r = sqrt(1.0 - u1 * u1);
const double phi = 2 * pi * u2;
return glm::vec3(cos(phi) * r, sin(phi) * r, u1);
}
@ -174,58 +186,58 @@ glm::vec3 reflect(const glm::vec3& I, const glm::vec3& N) {
}
std::optional<SceneResult> cast_scene(const Ray ray, Scene& scene, const bool use_bvh, const int depth) {
if(depth > max_depth)
if (depth > max_depth)
return {};
const std::function<decltype(test_scene)> scene_func = use_bvh ? test_scene_octree : test_scene;
if(auto hit = scene_func(ray, scene)) {
if (auto hit = scene_func(ray, scene)) {
const float diffuse = lighting::point_light(hit->position, light_position, hit->normal);
SceneResult result = {};
// direct lighting calculation
// currently only supports only one light (directional)
if(glm::dot(light_position - hit->position, hit->normal) > 0) {
if (glm::dot(light_position - hit->position, hit->normal) > 0) {
const glm::vec3 light_dir = glm::normalize(light_position - hit->position);
const Ray shadow_ray(hit->position + (hit->normal * light_bias), light_dir);
const float shadow = scene_func(shadow_ray, scene) ? 0.0f : 1.0f;
result.direct = hit->object->color * diffuse * shadow;
}
if(auto reflect_result = cast_scene(Ray(hit->position, glm::reflect(ray.direction, hit->normal)), scene, use_bvh, depth + 1))
if (auto reflect_result =
cast_scene(Ray(hit->position, glm::reflect(ray.direction, hit->normal)), scene, use_bvh, depth + 1))
result.reflect = reflect_result->combined;
// indirect lighting calculation
// we take a hemisphere orthogonal to the normal, and take a constant number of num_indirect_samples
// and naive monte carlo without PDF
if(num_indirect_samples > 0) {
for(int i = 0; i < num_indirect_samples; i++) {
if (num_indirect_samples > 0) {
for (int i = 0; i < num_indirect_samples; i++) {
const float theta = scene.distribution() * pi;
const float cos_theta = cos(theta);
const float sin_theta = sin(theta);
const auto [rotX, rotY] = orthogonal_system(hit->normal);
const glm::vec3 sampled_dir = hemisphere(cos_theta, sin_theta);
const glm::vec3 rotated_dir = {
glm::dot({rotX.x, rotY.x, hit->normal.x}, sampled_dir),
glm::dot({rotX.y, rotY.y, hit->normal.y}, sampled_dir),
glm::dot({rotX.z, rotY.z, hit->normal.z}, sampled_dir)
};
if(const auto indirect_result = cast_scene(Ray(ray.origin, rotated_dir), scene, use_bvh, depth + 1))
glm::dot({rotX.z, rotY.z, hit->normal.z}, sampled_dir)};
if (const auto indirect_result = cast_scene(Ray(ray.origin, rotated_dir), scene, use_bvh, depth + 1))
result.indirect += indirect_result->combined * cos_theta;
}
result.indirect /= num_indirect_samples;
}
result.hit = *hit;
result.combined = (result.indirect + result.direct + result.reflect);
return result;
} else {
return {};