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#include <glad/glad_compat.h>
#include <GLFW/glfw3.h>
#include <iostream>
#include <vector>
#include <cmath>
#include <type_traits>
#include <chrono>

GLFWAPI GLFWwindow* createWindow(int width, int height, const char* title) {
  GLFWwindow* window = nullptr;
  glfwSetErrorCallback([](int /*error_code*/, const char* description) {
    std::cerr << description << std::endl;
    std::exit(EXIT_FAILURE);
    });
  glfwInit();

  glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
  glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 6);
  glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_COMPAT_PROFILE);
  glfwWindowHint(GLFW_OPENGL_DEBUG_CONTEXT, true);
  window = glfwCreateWindow(width, height, title, NULL, NULL);

  if (!window) {
    std::cerr << "Failed to create GLFW window" << std::endl;
    glfwTerminate();
    std::exit(EXIT_FAILURE);
  }

  // Make the OpenGL context for this window be the currently associated context for this thread.
  glfwMakeContextCurrent(window);

  // Load the OpenGL API function pointers.
  if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) {
    std::cerr << "Failed to initialize GLAD" << std::endl;
    glfwDestroyWindow(window);
    glfwTerminate();
    std::exit(EXIT_FAILURE);
  }

  return window;
}

void checkShaderProgram(GLuint shader_program) {
  GLint status = GL_FALSE;
  glGetProgramiv(shader_program, GL_LINK_STATUS, &status);
  if (status == GL_FALSE) {
    GLchar info_log[4096];
    glGetProgramInfoLog(shader_program, sizeof(info_log), NULL, info_log);
    std::cerr << info_log << std::endl;
    std::exit(EXIT_FAILURE);
  }
};


const GLchar* shader_version_source = R"(
    // Start every shader with the GLSL version.
    #version 460 compatibility // OpenGL 4.6 Compatibility Profile
)";

const GLchar* vertex_output_source = R"(
    // Define a common struct that will be used to pass data from the vertex shader to the fragment shader.
    struct VSOutput {
      vec4 color;
    };
)";

struct ComputeShader {
  GLuint program;
  GLint height_uniform;
  GLint width_uniform;
  GLint frame_uniform;
};

struct FragmentShader {
  GLuint program;
};

ComputeShader setupComputeShader() {
  const GLchar* compute_shader_source = R"(
      // Compute shader to generate a rotation matrix.
      layout(local_size_x = 100, local_size_y = 1, local_size_z = 1) in;

      uniform uint height, width, frame;

      layout(binding = 1, std430) writeonly buffer ssbo { vec2 animations[]; };

      void main() {
        uint linear_index = gl_WorkGroupID.x * gl_WorkGroupSize.x + gl_LocalInvocationID.x;
        if (linear_index >= height * width) {
          return;
        }
        uint num_meshes = height, mesh = linear_index / width;
        uint num_instances = width, instance = linear_index % width;
        float instance_ratio = float(instance) / num_instances;
        float mesh_ratio = float(mesh) / num_meshes;
        float angle = 2*3.1415926f * ((mesh_ratio) + (instance_ratio)) + frame*0.01 + linear_index / float(num_meshes*num_instances);
        vec2 offset = 1*vec2(sin(angle) * (mesh_ratio), cos(angle) * (instance_ratio));
        animations[linear_index] = offset;
      }
    )";

  const GLchar* compute_shader_sources[]{ shader_version_source, compute_shader_source };
  GLuint compute_program = glCreateShaderProgramv(GL_COMPUTE_SHADER, (GLsizei)std::size(compute_shader_sources), compute_shader_sources);
  checkShaderProgram(compute_program);
  GLint height_uniform = glGetUniformLocation(compute_program, "height");
  GLint width_uniform = glGetUniformLocation(compute_program, "width");
  GLint frame_uniform = glGetUniformLocation(compute_program, "frame");
  return { compute_program, height_uniform, width_uniform, frame_uniform };
}


FragmentShader setupFragmentShader() {
  GLuint fragment_program;
  const GLchar* fragment_shader_source = R"(
    // Interpolated output from the vertex shader.
    in VSOutput vsOutput;

    // Just one output value. Automatically goes to the render target.
    out vec4 outColor;

    void main()
    {
      // output rgba = interpolated vertex rgba
      outColor = vsOutput.color;
    }
  )";

  const GLchar* fragment_shader_sources[]{ shader_version_source, vertex_output_source, fragment_shader_source };
  fragment_program = glCreateShaderProgramv(GL_FRAGMENT_SHADER, (GLsizei)std::size(fragment_shader_sources), fragment_shader_sources);
  checkShaderProgram(fragment_program);
  return { fragment_program };
}


enum Mode {
  MultiDrawElementsIndirect = 0,
  DrawElementsInstancedBaseVertexBaseInstance,
  DrawElementsInstanced,
  DrawElements,
  BeginEnd,
  num_modes
};

Mode mode = MultiDrawElementsIndirect;

void setDrawMode(Mode new_mode, GLFWwindow* window) {
  mode = new_mode;
  const char* mode_name{};
  switch (mode) {
    case MultiDrawElementsIndirect: mode_name = "glMultiDrawElementsIndirect"; break;
    case DrawElementsInstancedBaseVertexBaseInstance: mode_name = "glDrawElementsInstancedBaseVertexBaseInstance"; break;
    case DrawElementsInstanced: mode_name = "glDrawElementsInstanced"; break;
    case DrawElements: mode_name = "glDrawElements"; break;
    case BeginEnd: mode_name = "glBegin/glEnd"; break;
    default: mode_name = "Unknown"; break;
  }
  std::cout << "Switched to mode: " << mode_name << std::endl;
  glfwSetWindowTitle(window, (std::string("Lesson 2: A History of Draw Calls - ") + mode_name).c_str());
}

int main()
{
  GLFWwindow* window = createWindow(1024, 1024, "Lesson 5: A History of Draw Calls");

  struct Vec3 {
    GLfloat x;
    GLfloat y;
    GLfloat z;
  };

  struct RGBA8888 {
    GLubyte r;
    GLubyte g;
    GLubyte b;
    GLubyte a;
  };

  struct Vertex {
    Vec3 position;
    RGBA8888 color;
  };

  struct Triangle {
    GLushort v0;
    GLushort v1;
    GLushort v2;
  };

  struct SolidQuad {
    Vertex verts[4]{
      {{-0.01f,-0.01f,0.0f}, {255, 255, 255, 255}},
      {{+0.01f,-0.01f,0.0f}, {255, 255, 255, 255}},
      {{+0.01f,+0.01f,0.0f}, {255, 255, 255, 255}},
      {{-0.01f,+0.01f,0.0f}, {255, 255, 255, 255}},
    };
    Triangle tris[2]{
      {0, 1, 2},
      {0, 2, 3}
    };
    SolidQuad(float r, float g, float b, float a) {
      for (auto& v : verts) {
        v.color.r = static_cast<GLubyte>(r * 255);
        v.color.g = static_cast<GLubyte>(g * 255);
        v.color.b = static_cast<GLubyte>(b * 255);
        v.color.a = static_cast<GLubyte>(a * 255);
      }
    }
  };

  std::vector<Vertex> cpu_vertex_data;
  std::vector<Triangle> cpu_index_data;

  struct Mesh {
    unsigned int instance_count = 0;
    unsigned int base_index = 0;
    unsigned int index_count = 0;
    unsigned int base_vertex = 0;
    unsigned int vertex_count = 0;
  };
  std::vector<Mesh> meshes;
  constexpr size_t num_rows = 47, num_meshes = 100000, max_instances = 10;

  GLuint mesh_buffer = 0;
  GLint verts_buffer_offset = 0;
  glCreateBuffers(1, &mesh_buffer);
  {
    auto generateMesh = [](Vec3 bottom_left, Vec3 top_right, RGBA8888 c, GLuint num_rows, unsigned int num_instances, unsigned int base_vertex, unsigned int base_index, Vertex* dest_verts, GLushort* dest_indices)->Mesh {
      Vec3 row_delta{
        (top_right.x - bottom_left.x),
        (top_right.y - bottom_left.y) / static_cast<float>(num_rows),
        0.0f
      };
      Mesh mesh{
          num_instances,
          base_index,
          num_rows * 6,
          base_vertex,
          (num_rows + 1) * 2
      };
      Vec3 v0 = bottom_left;
      Vec3 v1 = { bottom_left.x + row_delta.x, bottom_left.y, bottom_left.z };
      RGBA8888 c0 = c;
      RGBA8888 c1 = c;
      dest_verts[mesh.base_vertex + 0] = Vertex{ v0, c0 };
      dest_verts[mesh.base_vertex + 1] = Vertex{ v1, c1 };
      for (unsigned int row = 0; row < num_rows; row++) {
        Vec3 v2 = { v0.x, v0.y + row_delta.y, v0.z };
        Vec3 v3 = { v1.x, v1.y + row_delta.y, v1.z };
        RGBA8888 c2 = { GLubyte(c0.r + 1), GLubyte(c0.g + 2), GLubyte(c0.b + 3), c0.a };
        RGBA8888 c3 = { GLubyte(c1.r + 1), GLubyte(c1.g + 2), GLubyte(c1.b + 3), c1.a };

        dest_verts[mesh.base_vertex + (row + 1) * 2 + 0] = Vertex{ v2, c2 };
        dest_verts[mesh.base_vertex + (row + 1) * 2 + 1] = Vertex{ v3, c3 };

        dest_indices[mesh.base_index + row * 6 + 0] = static_cast<GLushort>((row + 0) * 2 + 0);
        dest_indices[mesh.base_index + row * 6 + 1] = static_cast<GLushort>((row + 0) * 2 + 1);
        dest_indices[mesh.base_index + row * 6 + 2] = static_cast<GLushort>((row + 1) * 2 + 1);

        dest_indices[mesh.base_index + row * 6 + 3] = static_cast<GLushort>((row + 0) * 2 + 0);
        dest_indices[mesh.base_index + row * 6 + 4] = static_cast<GLushort>((row + 1) * 2 + 1);
        dest_indices[mesh.base_index + row * 6 + 5] = static_cast<GLushort>((row + 1) * 2 + 0);

        v0 = v2;
        v1 = v3;
        c0 = c2;
        c1 = c3;
      };
      return mesh;
    };

    size_t num_verts = num_meshes * (num_rows + 1) * 2;
    size_t num_indices = num_meshes * num_rows * 6;
    size_t vertex_bytes = num_verts * sizeof(Vertex);
    size_t index_bytes = num_indices * sizeof(GLushort);
    size_t total_bytes = vertex_bytes + index_bytes;

    cpu_vertex_data.assign(num_verts, Vertex{});
    cpu_index_data.assign(num_indices, Triangle{});
    GLushort* dest_indices = (GLushort*)(cpu_index_data.data());
    verts_buffer_offset = (GLint)index_bytes;
    Vertex* dest_verts = (Vertex*)(cpu_vertex_data.data());

    Mesh previous_mesh{};
    for (int i = 0; i < num_meshes; i++) {
      float width = 32.0f / num_meshes;
      Vec3 bottom_left{
        (i - 1)* width,
        -0.125f,
        0.0f
      };
      Vec3 top_right{
        (i + 1) * width,
        0.0125f,
        0.0f
      };
      previous_mesh = meshes.emplace_back(
        generateMesh(
          bottom_left,
          top_right,
          RGBA8888{ GLubyte(i*3), GLubyte(i * 2), GLubyte(i * 1), 255 },
          num_rows,
          max_instances,
          previous_mesh.base_vertex + previous_mesh.vertex_count,
          previous_mesh.base_index + previous_mesh.index_count,
          dest_verts,
          dest_indices
        )
      );
    }
    for (Mesh& mesh : meshes) {
      for (unsigned int i = 0; i < mesh.index_count; ++i) {
        ((GLushort*)cpu_index_data.data())[mesh.base_index + i] += mesh.base_vertex;
      }
      mesh.base_vertex = 0;
    }
    glNamedBufferStorage(mesh_buffer, total_bytes, nullptr, GL_MAP_WRITE_BIT);
    {
      GLubyte* mapped = (GLubyte*)glMapNamedBuffer(mesh_buffer, GL_WRITE_ONLY);
      memcpy(mapped, cpu_index_data.data(), index_bytes);
      memcpy(mapped + verts_buffer_offset, cpu_vertex_data.data(), vertex_bytes);
      glUnmapNamedBuffer(mesh_buffer);
    }
  }

  // https://www.khronos.org/opengl/wiki/Vertex_Rendering/Rendering_Failure
  // "The index buffer binding is stored within the VAO. If no VAO is bound, then you cannot bind a buffer object to GL_ELEMENT_ARRAY_BUFFER."
  GLuint vertex_array_object = 0;
  glCreateVertexArrays(1, &vertex_array_object);

  const GLuint mesh_buffer_binding = 0, position_attrib = 10, color_attrib = 11;
  glVertexArrayAttribBinding(vertex_array_object, position_attrib, mesh_buffer_binding);
  glVertexArrayAttribFormat(vertex_array_object, position_attrib, 3, GL_FLOAT, GL_FALSE, offsetof(Vertex, position));
  glEnableVertexArrayAttrib(vertex_array_object, position_attrib);

  glVertexArrayAttribBinding(vertex_array_object, color_attrib, mesh_buffer_binding);
  glVertexArrayAttribFormat(vertex_array_object, color_attrib, 4, GL_UNSIGNED_BYTE, GL_TRUE, offsetof(Vertex, color));
  glEnableVertexArrayAttrib(vertex_array_object, color_attrib);


  struct Vec2 {
    GLfloat x;
    GLfloat y;
  };
  GLuint animation_buffer = 0;
  glCreateBuffers(1, &animation_buffer);
  constexpr GLuint total_instances = num_meshes * max_instances;
  glNamedBufferStorage(animation_buffer, sizeof(Vec2[total_instances]), nullptr, GL_DYNAMIC_STORAGE_BIT);


  struct VertexShader {
    GLuint program;
    GLint manual_draw_id_uniform;
    GLint manual_base_instance_uniform;
    GLint manual_instance_uniform;
    GLint rotation_uniform;
  } vertex_shader;

  {
    const GLchar* vertex_shader_source = R"(
      layout (location = 10) in vec3 position;
      layout (location = 11) in vec4 color;
      layout (binding = 1, std430) readonly buffer ssbo2 { vec2 animations[]; };
      uniform uint manual_draw_id;
      uniform uint manual_base_instance;
      uniform uint manual_instance;
      uniform mat2x2 rotation_matrix;

      out gl_PerVertex {
          vec4 gl_Position;
      };

      // `vec4 gl_Position;` is implicitly defined in every vertex shader.
      // For additional outputs to the fragment shader, we need an `out` variable.
      out VSOutput vsOutput;

      void main() {
        uint base_instance = gl_BaseInstance + manual_base_instance;
        uint instance_id = gl_InstanceID + manual_instance;
        vec3 ur_position = position + gl_Vertex.xyz;
        vec4 ur_color = color + gl_Color;
        gl_Position.xy = rotation_matrix * ur_position.xy + animations[base_instance + instance_id];
        gl_Position.z = position.z;
        gl_Position.w = 1.0f;
        vsOutput.color = ur_color;
      }
    )";

    const GLchar* vertex_shader_sources[]{ shader_version_source, vertex_output_source, vertex_shader_source };
    GLuint vertex_program = glCreateShaderProgramv(GL_VERTEX_SHADER, (GLsizei)std::size(vertex_shader_sources), vertex_shader_sources);
    checkShaderProgram(vertex_program);
    GLint manual_draw_id_uniform = glGetUniformLocation(vertex_program, "manual_draw_id");
    GLint manual_base_instance_uniform = glGetUniformLocation(vertex_program, "manual_base_instance");
    GLint manual_instance_uniform = glGetUniformLocation(vertex_program, "manual_instance");
    GLint rotation_uniform = glGetUniformLocation(vertex_program, "rotation_matrix");
    vertex_shader = { vertex_program, manual_draw_id_uniform, manual_base_instance_uniform, manual_instance_uniform, rotation_uniform };
  }

  ComputeShader compute_shader = setupComputeShader();
  FragmentShader fragment_shader = setupFragmentShader();

  GLuint pipeline = 0;
  glGenProgramPipelines(1, &pipeline);
  glUseProgramStages(pipeline, GL_VERTEX_SHADER_BIT, vertex_shader.program);
  glUseProgramStages(pipeline, GL_FRAGMENT_SHADER_BIT, fragment_shader.program);

  constexpr GLuint anim_binding = 1;
  glBindBufferBase(GL_SHADER_STORAGE_BUFFER, anim_binding, animation_buffer);


  // https://registry.khronos.org/OpenGL-Refpages/gl4/html/glMultiDrawArraysIndirect.xhtml
  struct DrawElementsIndirectCommand {
    unsigned int count;
    unsigned int instanceCount;
    unsigned int firstIndex;
    int baseVertex;
    unsigned int baseInstance;
  };
  std::vector<DrawElementsIndirectCommand> cpu_commands_vector(num_meshes, {});

  GLuint command_buffer = 0;
  glCreateBuffers(1, &command_buffer);
  glNamedBufferStorage(command_buffer, cpu_commands_vector.size() * sizeof(DrawElementsIndirectCommand), nullptr, GL_DYNAMIC_STORAGE_BIT);

  setDrawMode(mode, window);
  glfwSetKeyCallback(window, [](GLFWwindow* window, int key, int scancode, int action, int mods) {
    if (action == GLFW_PRESS && key == GLFW_KEY_SPACE) {
      setDrawMode(Mode((mode + 1) % num_modes), window);
    }
  });

  auto start_time = std::chrono::high_resolution_clock::now();
  int start_frame = 0;

  for (int frame = 0; !glfwWindowShouldClose(window); frame++) {
    auto frame_time = std::chrono::high_resolution_clock::now();
    if (frame_time - start_time > std::chrono::seconds(1)) {
      float milliseconds_per_frame = std::chrono::duration<float, std::milli>(frame_time - start_time).count() / (frame - start_frame);
      std::cout << "Average frame time over last " << (frame - start_frame) << " frames: " << milliseconds_per_frame << " ms (" << 1000.0f / milliseconds_per_frame << " fps)" << std::endl;
      start_time = frame_time;
      start_frame = frame;
    }

    glClearColor(0.0f, 0.0f, 0.5f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    constexpr GLuint anims_width = 10;
    constexpr GLuint anims_height = total_instances / anims_width;
    glProgramUniform1ui(compute_shader.program, compute_shader.width_uniform, anims_width);
    glProgramUniform1ui(compute_shader.program, compute_shader.height_uniform, anims_height);
    glProgramUniform1ui(compute_shader.program, compute_shader.frame_uniform, frame);
    glUseProgram(compute_shader.program);
    glDispatchCompute(anims_height, 1, 1);
    glMemoryBarrier(GL_SHADER_STORAGE_BARRIER_BIT);
    glUseProgram(0);

    struct Mat2x2 {
      GLfloat m00, m01;
      GLfloat m10, m11;
    };
    float angle = frame * -0.003f;
    Mat2x2 rotation_matrix = {
      std::cos(angle), -std::sin(angle),
      std::sin(angle),  std::cos(angle)
    };
    glProgramUniformMatrix2fv(vertex_shader.program, vertex_shader.rotation_uniform, 1, false, (const float*)&rotation_matrix);
    glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_base_instance_uniform, 0);
    glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_instance_uniform, 0);
    glBindProgramPipeline(pipeline);

    glBindVertexArray(vertex_array_object);
    const GLsizei bind_count = 1;
    const GLuint bind_buffers[bind_count] = { mesh_buffer };
    const GLintptr bind_offsets[bind_count] = { verts_buffer_offset };
    const GLsizei bind_strides[bind_count] = { sizeof(Vertex) };
    glVertexArrayVertexBuffers(vertex_array_object, mesh_buffer_binding, bind_count, bind_buffers, bind_offsets, bind_strides);
    glVertexArrayElementBuffer(vertex_array_object, mesh_buffer);

    GLuint base_instance = 0;
    GLsizei draw_count = 0;
    glfwSwapInterval(0); // Disable vsync.
    for (const Mesh& mesh : meshes) {
      cpu_commands_vector[draw_count++] = { mesh.index_count, mesh.instance_count, mesh.base_index, (int)mesh.base_vertex, base_instance };
      base_instance += mesh.instance_count;
    }

    glColor4f(0, 0, 0, 0);
    glVertex4f(0, 0, 0, 0);

    switch (mode) {
      case MultiDrawElementsIndirect:{
        glNamedBufferSubData(command_buffer, 0, cpu_commands_vector.size() * sizeof(cpu_commands_vector[0]), cpu_commands_vector.data());
        glBindBuffer(GL_DRAW_INDIRECT_BUFFER, command_buffer);
        glMultiDrawElementsIndirect(GL_TRIANGLES, GL_UNSIGNED_SHORT, 0, draw_count, 0);
      } break;
      case DrawElementsInstancedBaseVertexBaseInstance: {
        for (DrawElementsIndirectCommand& command : cpu_commands_vector) {
          glDrawElementsInstancedBaseVertexBaseInstance(
            GL_TRIANGLES,
            command.count,
            GL_UNSIGNED_SHORT,
            (const GLvoid*)(command.firstIndex * sizeof(GLushort)),
            command.instanceCount,
            command.baseVertex,
            command.baseInstance
          );
        }
      } break;
      case DrawElementsInstanced: {
        GLuint draw_id = 0, base_instance = 0;
        for (DrawElementsIndirectCommand& command : cpu_commands_vector) {
          glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_draw_id_uniform, draw_id);
          glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_base_instance_uniform, base_instance);
          glDrawElementsInstanced(
            GL_TRIANGLES,
            command.count,
            GL_UNSIGNED_SHORT,
            (const GLvoid*)(command.firstIndex * sizeof(GLushort)),
            command.instanceCount
          );
          draw_id++;
          base_instance += command.instanceCount;
        }
      } break;
      case DrawElements: {
        GLuint draw_id = 0, base_instance = 0;
        for (DrawElementsIndirectCommand& command : cpu_commands_vector) {
          glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_draw_id_uniform, draw_id);
          glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_base_instance_uniform, base_instance);
          for (unsigned int instance = 0; instance < command.instanceCount; ++instance) {
            glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_instance_uniform, instance);
            glDrawElements(
              GL_TRIANGLES,
              command.count,
              GL_UNSIGNED_SHORT,
              (const GLvoid*)(command.firstIndex * sizeof(GLushort))
            );
            base_instance++;
          }
          draw_id++;
        }
      } break;
      case BeginEnd: {
        GLuint draw_id = 0, base_instance = 0;
        for (DrawElementsIndirectCommand& command : cpu_commands_vector) {
          glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_draw_id_uniform, draw_id);
          glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_base_instance_uniform, base_instance);
          for (unsigned int instance = 0; instance < command.instanceCount; ++instance) {
            glProgramUniform1ui(vertex_shader.program, vertex_shader.manual_instance_uniform, instance);
            glBegin(GL_TRIANGLES);
            const GLushort* indices = ((GLushort*)cpu_index_data.data()) + command.firstIndex;
            for (unsigned int i = 0; i < command.count; ++i) {
              GLushort index = indices[i];
              const Vertex& v = cpu_vertex_data[index];
              glColor4ubv((const GLubyte*)&v.color);
              glVertex3fv((const GLfloat*)&v.position);
            }
            glEnd();
            base_instance++;
          }
          draw_id++;
        }
      } break;
      default:
        break;
    }
    glfwSwapBuffers(window);
    glfwPollEvents();
  }

  // We could just let process termination clean everything up for us.
  // But, let's manually clean up our resources just to be explicit.
  glDeleteVertexArrays(1, &vertex_array_object);
  glDeleteProgramPipelines(1, &pipeline);
  glDeleteProgram(compute_shader.program);
  glDeleteProgram(fragment_shader.program);
  glDeleteProgram(vertex_shader.program);
  GLuint buffers_to_delete[] = { command_buffer, animation_buffer, mesh_buffer };
  glDeleteBuffers(std::size(buffers_to_delete), buffers_to_delete);

  // Shut down and clean up everything we did with GLFW.
  glfwTerminate();
  // Exit the program.
  return 0;
}
Edit

Pub: 16 Oct 2025 15:59 UTC

Edit: 17 Oct 2025 20:39 UTC

Views: 47