src/main.cpp

@@ -2,32 +2,46 @@
 #include "cpu/CPURenderer.h"
 #include "metal/MetalRenderer.h"
 #include "util/ModelLoader.h"
+#include "util/CLI.h"
 #include <imgui.h>
 
-int main()
+int main(int argc, const char* argv[])
 {
+  // Parse command-line arguments
+  CLIOptions cliOpts = CLI::parseArgs(argc, argv);
+
+  // If help was requested, just exit after printing
+  if (cliOpts.showHelp)
+  {
+    return 0;
+  }
+
   std::unique_ptr<Renderer> renderer = std::make_unique<MetalRenderer>();
+
+  // Add lights from CLI (use defaults if none specified)
+  if (cliOpts.directionalLights.empty() && cliOpts.pointLights.empty())
+  {
+    // Default lights if no CLI lights specified
     renderer->addDirectionalLight(DirectionalLight{
         .direction = glm::normalize(glm::vec3(-0.4f, -0.3f, -0.2f)),
         .color = glm::vec3(1, 1, 1),
     });
     renderer->addPointLight(PointLight{});
+  }
+  else
+  {
+    CLI::applyLights(renderer.get(), cliOpts);
+  }
+
   renderer->addModels(ModelLoader::loadModel("../res/models/stanford-bunny.obj"),
                       glm::mat4(glm::vec4(1.0f, 0.0f, 0.0f, 0.0f), glm::vec4(0.0f, 1.0f, 0.0f, 0.0f), glm::vec4(0.0f, 0.0f, 1.0f, 0.0f),
                                 glm::vec4(0.0f, 0.0f, 0.0f, 1.0f)));
   renderer->generate();
-  Camera camera = Camera{
+
-      .position = glm::vec3(2, 1, 2),
+  // Create camera and render parameters from CLI options
-      .target = glm::vec3(0, 0, 0),
+  Camera camera = CLI::toCamera(cliOpts);
-      .f = 0,
+  RenderParameter render = CLI::toRenderParameter(cliOpts);
-      .A = 0,
+
-      .S_O = 6,
-  };
-  RenderParameter render = RenderParameter{
-      .width = 1920,
-      .height = 1080,
-      .numSamples = 10000,
-  };
   renderer->startRender(camera, render);
 
   while (true)

src/metal/MetalRenderer.mm

@@ -195,10 +195,10 @@ void MetalRenderer::render(Camera camera, RenderParameter parameter)
       .f = camera.f,
       .cameraForward = camera.target - camera.position,
       .S_O = camera.S_O,
-      .fogEmm = glm::vec3(0, 0, 0),
+      .fogEmm = camera.fogEmm,
-      .ks = 0,
+      .ks = camera.ks,
       .A = camera.A,
-      .ka = 0,
+      .ka = camera.ka,
       .sensorSize = camera.sensorSize,
       .width = parameter.width,
       .height = parameter.height,

src/util/CLI.cpp

@@ -0,0 +1,353 @@
+#include "CLI.h"
+#include <sstream>
+#include <iostream>
+#include <algorithm>
+#include <cmath>
+
+namespace CLI
+{
+    namespace
+    {
+        float parseFloat(const std::string& str, const std::string& argName)
+        {
+            try
+            {
+                return std::stof(str);
+            }
+            catch (const std::exception& e)
+            {
+                std::cerr << "Error: Invalid float value for " << argName << ": " << str << "\n";
+                return 0.0f;
+            }
+        }
+
+        uint32_t parseUInt(const std::string& str, const std::string& argName)
+        {
+            try
+            {
+                return static_cast<uint32_t>(std::stoul(str));
+            }
+            catch (const std::exception& e)
+            {
+                std::cerr << "Error: Invalid unsigned integer value for " << argName << ": " << str << "\n";
+                return 0;
+            }
+        }
+
+        glm::vec3 parseVec3(const std::vector<std::string>& tokens, size_t offset, const std::string& argName)
+        {
+            if (offset + 3 > tokens.size())
+            {
+                std::cerr << "Error: " << argName << " requires 3 float values (x y z)\n";
+                return glm::vec3(0, 0, 0);
+            }
+            return glm::vec3(
+                parseFloat(tokens[offset], argName + " x"),
+                parseFloat(tokens[offset + 1], argName + " y"),
+                parseFloat(tokens[offset + 2], argName + " z")
+            );
+        }
+
+        glm::vec2 parseVec2(const std::vector<std::string>& tokens, size_t offset, const std::string& argName)
+        {
+            if (offset + 2 > tokens.size())
+            {
+                std::cerr << "Error: " << argName << " requires 2 float values\n";
+                return glm::vec2(0, 0);
+            }
+            return glm::vec2(
+                parseFloat(tokens[offset], argName + " x"),
+                parseFloat(tokens[offset + 1], argName + " y")
+            );
+        }
+    }
+
+    void printHelp()
+    {
+        std::cout << R"(
+Usage: RayTracer [options]
+
+Render Parameters:
+  -w, --width <int>          Image width (default: 1920)
+  -h, --height <int>         Image height (default: 1080)
+  -s, --samples <int>        Number of samples per pixel (default: 10000)
+  -b, --bounces <int>        Maximum ray bounces (default: 4)
+  --bg-color <r> <g> <b>     Background/sky color (default: 0.05 0.05 0.1)
+  --throughput <float>       Minimum throughput threshold (default: 0.01)
+  -o, --output <file>        Output image file path (PGM format)
+
+Camera Parameters:
+  --cam-pos <x> <y> <z>      Camera position (default: 2 1 2)
+  --cam-target <x> <y> <z>   Camera target (default: 0 0 0)
+  --cam-focal <float>        Focal length (default: 0.7)
+  --cam-aperture <float>     Aperture size (default: 0.35)
+  --cam-distance <float>     Subject distance S_O (default: 20)
+  --cam-sensor <w> <h>       Sensor size (default: 0.036 0.024)
+
+Camera Shading Parameters:
+  --fog-emission <r> <g> <b> Fog emission color (default: 0 0 0)
+  --specular-coeff <float>   Specular coefficient ks (default: 0)
+  --ambient-coeff <float>    Ambient coefficient ka (default: 0)
+
+Light Parameters:
+  --dir-light <dx> <dy> <dz> <r> <g> <b>
+                             Add directional light (direction + color)
+  --point-light <x> <y> <z> <r> <g> <b> <att>
+                             Add point light (position + color + attenuation)
+
+Other:
+  --help                     Show this help message
+
+Examples:
+  RayTracer -w 1280 -h 720 -s 1000
+  RayTracer --cam-pos 3 2 3 --cam-focal 0.5
+  RayTracer --dir-light -0.4 -0.3 -0.2 1 1 1
+  RayTracer --point-light 0 5 0 1 0.5 0 0.5
+  RayTracer --fog-emission 0.1 0.2 0.3 --specular-coeff 0.5 --ambient-coeff 0.2
+  RayTracer -b 8 --bg-color 0.1 0.1 0.2 -o output.pgm
+)";
+    }
+
+    CLIOptions parseArgs(int argc, const char* argv[])
+    {
+        CLIOptions options;
+        std::vector<std::string> args;
+        for (int i = 1; i < argc; ++i)
+        {
+            args.push_back(argv[i]);
+        }
+
+        size_t i = 0;
+        while (i < args.size())
+        {
+            const std::string& arg = args[i];
+
+            if (arg == "--help")
+            {
+                options.showHelp = true;
+                printHelp();
+                return options;
+            }
+            else if (arg == "--width" || arg == "-w")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --width requires a value\n";
+                    return options;
+                }
+                options.width = parseUInt(args[++i], "width");
+            }
+            else if (arg == "--height" || arg == "-h")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --height requires a value\n";
+                    return options;
+                }
+                options.height = parseUInt(args[++i], "height");
+            }
+            else if (arg == "--samples" || arg == "-s")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --samples requires a value\n";
+                    return options;
+                }
+                options.numSamples = parseUInt(args[++i], "samples");
+            }
+            else if (arg == "--bounces" || arg == "-b")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --bounces requires a value\n";
+                    return options;
+                }
+                options.maxBounces = parseUInt(args[++i], "bounces");
+            }
+            else if (arg == "--bg-color")
+            {
+                if (i + 3 >= args.size())
+                {
+                    std::cerr << "Error: --bg-color requires 3 values (r g b)\n";
+                    return options;
+                }
+                options.backgroundColor = parseVec3(args, i + 1, "bg-color");
+                i += 3;
+            }
+            else if (arg == "--throughput")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --throughput requires a value\n";
+                    return options;
+                }
+                options.throughputThreshold = parseFloat(args[++i], "throughput");
+            }
+            else if (arg == "--output" || arg == "-o")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --output requires a file path\n";
+                    return options;
+                }
+                options.outputFile = args[++i];
+            }
+            else if (arg == "--cam-pos")
+            {
+                if (i + 3 >= args.size())
+                {
+                    std::cerr << "Error: --cam-pos requires 3 values (x y z)\n";
+                    return options;
+                }
+                options.camPosition = parseVec3(args, i + 1, "cam-pos");
+                i += 3;
+            }
+            else if (arg == "--cam-target")
+            {
+                if (i + 3 >= args.size())
+                {
+                    std::cerr << "Error: --cam-target requires 3 values (x y z)\n";
+                    return options;
+                }
+                options.camTarget = parseVec3(args, i + 1, "cam-target");
+                i += 3;
+            }
+            else if (arg == "--cam-focal")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --cam-focal requires a value\n";
+                    return options;
+                }
+                options.camFocalLength = parseFloat(args[++i], "cam-focal");
+            }
+            else if (arg == "--cam-aperture")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --cam-aperture requires a value\n";
+                    return options;
+                }
+                options.camAperture = parseFloat(args[++i], "cam-aperture");
+            }
+            else if (arg == "--cam-distance")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --cam-distance requires a value\n";
+                    return options;
+                }
+                options.camDistance = parseFloat(args[++i], "cam-distance");
+            }
+            else if (arg == "--cam-sensor")
+            {
+                if (i + 2 >= args.size())
+                {
+                    std::cerr << "Error: --cam-sensor requires 2 values (w h)\n";
+                    return options;
+                }
+                options.camSensorSize = parseVec2(args, i + 1, "cam-sensor");
+                i += 2;
+            }
+            else if (arg == "--fog-emission")
+            {
+                if (i + 3 >= args.size())
+                {
+                    std::cerr << "Error: --fog-emission requires 3 values (r g b)\n";
+                    return options;
+                }
+                options.fogEmission = parseVec3(args, i + 1, "fog-emission");
+                i += 3;
+            }
+            else if (arg == "--specular-coeff")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --specular-coeff requires a value\n";
+                    return options;
+                }
+                options.specularCoeff = parseFloat(args[++i], "specular-coeff");
+            }
+            else if (arg == "--ambient-coeff")
+            {
+                if (i + 1 >= args.size())
+                {
+                    std::cerr << "Error: --ambient-coeff requires a value\n";
+                    return options;
+                }
+                options.ambientCoeff = parseFloat(args[++i], "ambient-coeff");
+            }
+            else if (arg == "--dir-light")
+            {
+                if (i + 6 > args.size())
+                {
+                    std::cerr << "Error: --dir-light requires 6 values (dx dy dz r g b)\n";
+                    return options;
+                }
+                DirectionalLight light;
+                light.direction = parseVec3(args, i + 1, "dir-light direction");
+                light.color = parseVec3(args, i + 4, "dir-light color");
+                options.directionalLights.push_back(light);
+                i += 6;
+            }
+            else if (arg == "--point-light")
+            {
+                if (i + 7 > args.size())
+                {
+                    std::cerr << "Error: --point-light requires 7 values (x y z r g b attenuation)\n";
+                    return options;
+                }
+                PointLight light;
+                light.position = parseVec3(args, i + 1, "point-light position");
+                light.color = parseVec3(args, i + 4, "point-light color");
+                light.attenuation = parseFloat(args[i + 7], "point-light attenuation");
+                options.pointLights.push_back(light);
+                i += 7;
+            }
+            else
+            {
+                std::cerr << "Warning: Unknown argument: " << arg << "\n";
+            }
+
+            ++i;
+        }
+
+        return options;
+    }
+
+    Camera toCamera(const CLIOptions& opts)
+    {
+        return Camera{
+            .position = opts.camPosition,
+            .target = opts.camTarget,
+            .sensorSize = opts.camSensorSize,
+            .S_O = opts.camDistance,
+            .f = opts.camFocalLength,
+            .A = opts.camAperture,
+            .fogEmm = opts.fogEmission,
+            .ks = opts.specularCoeff,
+            .ka = opts.ambientCoeff
+        };
+    }
+
+    RenderParameter toRenderParameter(const CLIOptions& opts)
+    {
+        return RenderParameter{
+            .width = opts.width,
+            .height = opts.height,
+            .numSamples = opts.numSamples
+        };
+    }
+
+    void applyLights(Renderer* renderer, const CLIOptions& opts)
+    {
+        for (const auto& dirLight : opts.directionalLights)
+        {
+            renderer->addDirectionalLight(dirLight);
+        }
+        for (const auto& pointLight : opts.pointLights)
+        {
+            renderer->addPointLight(pointLight);
+        }
+    }
+}

src/util/CLI.h

@@ -0,0 +1,55 @@
+#pragma once
+#include "Camera.h"
+#include "scene/Renderer.h"
+#include <string>
+#include <vector>
+#include <glm/glm.hpp>
+
+struct CLIOptions
+{
+    // Render parameters
+    uint32_t width = 1920;
+    uint32_t height = 1080;
+    uint32_t numSamples = 10000;
+    uint32_t maxBounces = 4;
+    glm::vec3 backgroundColor = glm::vec3(0.05f, 0.05f, 0.1f);
+    float throughputThreshold = 0.01f;
+    std::string outputFile;
+
+    // Camera parameters
+    glm::vec3 camPosition = glm::vec3(2, 1, 2);
+    glm::vec3 camTarget = glm::vec3(0, 0, 0);
+    float camFocalLength = 0.7f;
+    float camAperture = 0.35f;
+    float camDistance = 20.0f;
+    glm::vec2 camSensorSize = glm::vec2(0.036f, 0.024f);
+
+    // Camera shading parameters
+    glm::vec3 fogEmission = glm::vec3(0, 0, 0);
+    float specularCoeff = 0.0f;
+    float ambientCoeff = 0.0f;
+
+    // Light parameters
+    std::vector<DirectionalLight> directionalLights;
+    std::vector<PointLight> pointLights;
+
+    bool showHelp = false;
+};
+
+namespace CLI
+{
+    // Parse command-line arguments and return CLIOptions
+    CLIOptions parseArgs(int argc, const char* argv[]);
+
+    // Print help message
+    void printHelp();
+
+    // Convert CLIOptions to Camera struct
+    Camera toCamera(const CLIOptions& opts);
+
+    // Convert CLIOptions to RenderParameter struct
+    RenderParameter toRenderParameter(const CLIOptions& opts);
+
+    // Apply lights from CLIOptions to renderer
+    void applyLights(Renderer* renderer, const CLIOptions& opts);
+}

src/util/CMakeLists.txt

@@ -3,6 +3,8 @@ target_sources(RayTracer
 		BRDF.h
 		BRDF.cpp
 		Camera.h
+		CLI.h
+		CLI.cpp
 		Material.h
 		Material.cpp
 		Model.h

src/util/Camera.h

@@ -9,4 +9,7 @@ struct Camera
     float S_O = 20;
     float f = 0.7;
     float A = 0.35;
+    glm::vec3 fogEmm = glm::vec3(0, 0, 0);
+    float ks = 0;
+    float ka = 0;
 };