[feat]: complete RHI api

1 files changed, 0 insertions, 625 deletions

diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
deleted file mode 100644
index bf5a2b6..0000000
--- a/src/engine/engine.cpp
+++ /dev/null
@@ -1,625 +0,0 @@
-#include <iostream>
-#include <fstream>
-#include <sstream>
-
-#include <GLFW/glfw3.h>
-#include <glad/glad.h>
-
-#define STB_IMAGE_WRITE_IMPLEMENTATION
-#include "stb_image_write.h"
-
-#include "engine.h"
-#include "core/log.h"
-#include "core/hdri_manager.h"
-#include "rendering/vertex_buffer.h"
-#include "rendering/index_buffer.h"
-
-namespace Donut
-{
-    Engine::Engine()
-        : m_sag_a(glm::vec3(0.0f, 0.0f, 0.0f), 8.54e36f)
-    {
-        m_width = 1280;
-        m_height = 720;
-
-        m_camera.set_camera_mode(CameraMode::Orbital);
-        m_camera.set_orbital_radius(1e11);
-        m_camera.set_orbital_limits(1e9, 1e13);
-        m_camera.set_orbital_speed(0.01f);
-        m_camera.set_zoom_speed(1e10f);
-
-        m_objects =
-        {
-            { glm::vec4(0.00f, 0.00f, 0.00f, m_sag_a.m_rs), glm::vec4(0, 0, 0, 1), static_cast<float>(m_sag_a.m_mass) }
-        };
-
-        // The geodesic ray tracer used to be a compute shader; it is now a
-        // fullscreen vertex+fragment pass (see dispatch_compute) so it runs on
-        // macOS OpenGL 4.1, which has no compute shaders.
-        m_compute_program = Ref<Shader>(Shader::create("assets/shaders/Geodesic.glsl"));
-        m_shader_program  = Ref<Shader>(Shader::create("assets/shaders/TexturedQuad.glsl"));
-        m_blur_shader     = Ref<Shader>(Shader::create("assets/shaders/Blur.glsl"));
-
-        auto& hdri_manager = HDRIManager::get();
-        m_hdri_environment = hdri_manager.get_current_hdri();
-        if (!m_hdri_environment)
-        {
-            hdri_manager.set_current_hdri("assets/hdri/HDR_blue_nebulae-1.hdr");
-            m_hdri_environment = hdri_manager.get_current_hdri();
-            if (!m_hdri_environment)
-                DONUT_WARN("Failed to load default HDRI, using fallback");
-        }
-
-        m_camera_ubo = UniformBuffer::create(128, 1);
-        m_disk_ubo   = UniformBuffer::create(sizeof(float) * 6, 2);  // r1,r2,turbulence,thickness,brightness,temperature
-
-        uint32_t obj_ubo_size = sizeof(int) + 3 * sizeof(float)
-            + 16 * (sizeof(glm::vec4) + sizeof(glm::vec4))
-            + 16 * sizeof(float);
-        m_objects_ubo = UniformBuffer::create(obj_ubo_size, 3);
-
-        m_simulation_ubo = UniformBuffer::create(sizeof(int) * 2 + sizeof(float) * 2, 4);
-
-        auto result = QuadVAO();
-        m_quad_vao = result.first;
-        m_texture = result.second;
-
-        // GLSL 4.10 forbids explicit binding qualifiers on uniform blocks, so
-        // associate the geodesic shader's blocks with their UBO binding points
-        // from the host side instead.
-        if (m_compute_program)
-        {
-            uint32_t prog = m_compute_program->get_renderer_id();
-            struct { const char* name; uint32_t point; } blocks[] =
-            {
-                { "Camera", 1 }, { "Disk", 2 }, { "Objects", 3 }, { "Simulation", 4 }
-            };
-            for (const auto& b : blocks)
-            {
-                uint32_t idx = glGetUniformBlockIndex(prog, b.name);
-                if (idx != GL_INVALID_INDEX)
-                    glUniformBlockBinding(prog, idx, b.point);
-            }
-        }
-
-        glGenFramebuffers(1, &m_geodesic_fbo);
-    }
-
-    auto Engine::update_window_dimensions() -> void
-    {
-        update_compute_dimensions();
-    }
-
-    auto Engine::set_window_dimensions(int width, int height) -> void
-    {
-        int old_width = m_width;
-        int old_height = m_height;
-        int old_compute_height = m_compute_height;
-
-        m_width = width;
-        m_height = height;
-
-        if (old_width         != m_width  ||
-            old_height        != m_height ||
-            old_compute_height != m_compute_height)
-            update_compute_dimensions();
-    }
-
-    auto Engine::update_performance(float delta_time) -> void
-    {
-        if (delta_time > 0.0f)
-            m_current_fps = 1.0f / delta_time;
-    }
-
-    auto Engine::update_compute_dimensions() -> void
-    {
-        m_texture = Texture2D::create(get_compute_width(), m_compute_height);
-    }
-
-    auto Engine::draw_full_screen_quad() -> void
-    {
-        RenderCommand::set_viewport(0, 0, m_width, m_height);
-
-        m_shader_program->bind();
-        m_quad_vao->bind();
-
-        m_texture->bind(0);
-        m_shader_program->set_int("u_ScreenTexture", 0);
-
-        RenderCommand::disable_depth_test();
-        RenderCommand::draw_arrays(6);
-        RenderCommand::enable_depth_test();
-    }
-
-    auto Engine::draw_blur_pass() -> void
-    {
-        RenderCommand::set_viewport(0, 0, m_width, m_height);
-
-        m_blur_shader->bind();
-        m_quad_vao->bind();
-
-        m_texture->bind(0);
-        m_blur_shader->set_int("u_ScreenTexture", 0);
-        m_blur_shader->set_float2("u_Resolution", glm::vec2(m_width, m_height));
-        m_blur_shader->set_float("u_BlurStrength", m_blur_strength);
-        m_blur_shader->set_float("u_GlowIntensity", m_glow_intensity);
-
-        RenderCommand::disable_depth_test();
-        RenderCommand::draw_arrays(6);
-        RenderCommand::enable_depth_test();
-    }
-
-    auto Engine::draw_geodesic_pass(int cw, int ch) -> void
-    {
-        m_quad_vao->bind();
-        RenderCommand::disable_depth_test();
-
-#ifdef __APPLE__
-        // macOS aborts any GPU submission that runs longer than a couple of
-        // seconds ("GPU Hang"). The geodesic ray-marcher can far exceed that in
-        // a single fullscreen draw, so render it in scissored tiles and flush
-        // after each, keeping every submission short enough to survive the
-        // watchdog. Compute-capable platforms draw it in one pass.
-        // Largest tile that keeps a tile's worst-case work (tile^2 * step_cap)
-        // inside the safe watchdog zone measured on this GPU (~25M pixel-steps
-        // per submission); bigger tiles mean fewer glFinish stalls.
-        const int tile = 64;
-        glEnable(GL_SCISSOR_TEST);
-        for (int y = 0; y < ch; y += tile)
-        {
-            int th = std::min(tile, ch - y);
-            for (int x = 0; x < cw; x += tile)
-            {
-                int tw = std::min(tile, cw - x);
-                glScissor(x, y, tw, th);
-                RenderCommand::draw_arrays(6);
-                glFinish();
-            }
-        }
-        glDisable(GL_SCISSOR_TEST);
-#else
-        RenderCommand::draw_arrays(6);
-#endif
-
-        RenderCommand::enable_depth_test();
-    }
-
-    auto Engine::dispatch_compute(const Camera& cam) -> void
-    {
-        auto& hdri_manager = HDRIManager::get();
-        m_hdri_environment = hdri_manager.get_current_hdri();
-
-        int cw = get_compute_width();
-        int ch = m_compute_height;
-
-        // Render the geodesic pass into m_texture through an FBO. This replaces
-        // the old compute dispatch + image_store path, which relied on OpenGL
-        // 4.3 compute and 4.2 image load/store that macOS does not provide.
-        glBindFramebuffer(GL_FRAMEBUFFER, m_geodesic_fbo);
-        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, m_texture->get_renderer_id(), 0);
-        glViewport(0, 0, cw, ch);
-
-        m_compute_program->bind();
-        upload_camera_ubo(cam);
-        upload_disk_ubo();
-        upload_objects_ubo(m_objects);
-        upload_simulation_ubo();
-        m_compute_program->set_float2("u_Resolution", glm::vec2(static_cast<float>(cw), static_cast<float>(ch)));
-
-        if (m_hdri_environment)
-        {
-            m_hdri_environment->bind(5);
-            m_compute_program->set_int("u_HDRIEnvironment", 5);
-        }
-
-        draw_geodesic_pass(cw, ch);
-
-        glBindFramebuffer(GL_FRAMEBUFFER, 0);
-    }
-
-    auto Engine::upload_camera_ubo(const Camera& cam) -> void
-    {
-        struct UBOData
-        {
-            glm::vec3 pos;     float _pad0;
-            glm::vec3 right;   float _pad1;
-            glm::vec3 up;      float _pad2;
-            glm::vec3 forward; float _pad3;
-            float tan_half_fov;
-            float aspect;
-            bool  moving;
-            int   _pad4;
-        } data;
-
-        glm::vec3 pos, fwd;
-        if (cam.get_camera_mode() == CameraMode::FPS)
-        {
-            pos = cam.get_position();
-            fwd = cam.get_forward_direction();
-        }
-        else
-        {
-            pos = cam.get_orbital_position();
-            fwd = glm::normalize(cam.get_orbital_target() - pos);
-        }
-        glm::vec3 right = glm::normalize(glm::cross(fwd, glm::vec3(0, 1, 0)));
-        glm::vec3 up    = glm::cross(right, fwd);
-
-        data.pos        = pos;
-        data.right      = right;
-        data.up         = up;
-        data.forward    = fwd;
-        data.tan_half_fov = static_cast<float>(tan(glm::radians(m_bh.fov_degrees * 0.5f)));
-        data.aspect     = static_cast<float>(get_compute_width()) / static_cast<float>(m_compute_height);
-        data.moving     = cam.is_dragging() || cam.is_panning();
-
-        m_camera_ubo->set_data(&data, sizeof(UBOData));
-        m_camera_ubo->bind(1);
-    }
-
-    auto Engine::upload_objects_ubo(const std::vector<ObjectData>& objs) -> void
-    {
-        struct UBOData
-        {
-            int num_objects;
-            float _pad0, _pad1, _pad2;
-            glm::vec4 pos_radius[16];
-            glm::vec4 color[16];
-            float mass[16];
-        } data;
-
-        size_t count = std::min(objs.size(), size_t(16));
-        data.num_objects = static_cast<int>(count);
-
-        for (size_t i = 0; i < count; ++i)
-        {
-            data.pos_radius[i] = objs[i].m_pos_radius;
-            data.color[i] = objs[i].m_color;
-            data.mass[i] = objs[i].m_mass;
-        }
-
-        m_objects_ubo->set_data(&data, sizeof(data));
-        m_objects_ubo->bind(3);
-    }
-
-    auto Engine::upload_disk_ubo() -> void
-    {
-        // Layout matches the shared Geodesic Disk struct (same as Vulkan). Radii
-        // are in Schwarzschild radii x the shader's SagA_rs constant (1.269e10).
-        const float rs = 1.269e10f;
-        float disk_data[6] = {
-            std::max(m_bh.disk_inner_rs, 3.0f) * rs,
-            std::max(m_bh.disk_outer_rs, m_bh.disk_inner_rs + 0.5f) * rs,
-            std::max(m_bh.turbulence, 0.0f),
-            rs * 0.1f,                              // slab half-thickness (fixed)
-            std::max(m_bh.brightness, 0.0f),
-            std::max(m_bh.temperature, 1000.0f),
-        };
-        m_disk_ubo->set_data(disk_data, sizeof(disk_data));
-        m_disk_ubo->bind(2);
-    }
-
-    auto Engine::upload_simulation_ubo() -> void
-    {
-        struct UBOData
-        {
-            int max_steps_moving;
-            int max_steps_static;
-            float early_exit_distance;
-            float time;
-        } data;
-
-        data.max_steps_moving    = m_bh.quality_steps;
-        data.max_steps_static    = m_bh.quality_steps;   // resolution/tiling is the lever, not step count
-        data.early_exit_distance = m_early_exit_distance;
-        data.time              = static_cast<float>(glfwGetTime()) * m_rotation_speed;
-
-#ifdef __APPLE__
-        // macOS has no compute shaders, so the geodesic pass runs as a tiled
-        // fragment shader under the OS GPU watchdog. Cap the step count so a
-        // single 64px tile stays under the safe per-submission budget (~25M
-        // pixel-steps); Windows/Linux keep the full count.
-        data.max_steps_moving = std::min(data.max_steps_moving, 6000);
-        data.max_steps_static = std::min(data.max_steps_static, 6000);
-#endif
-
-        m_simulation_ubo->set_data(&data, sizeof(data));
-        m_simulation_ubo->bind(4);
-    }
-
-    auto Engine::update_physics(float delta_time) -> void
-    {
-        for (auto& obj : m_objects)
-        {
-            for (auto& obj2 : m_objects)
-            {
-                if (&obj == &obj2) continue;
-                float dx = obj2.m_pos_radius.x - obj.m_pos_radius.x;
-                float dy = obj2.m_pos_radius.y - obj.m_pos_radius.y;
-                float dz = obj2.m_pos_radius.z - obj.m_pos_radius.z;
-                float distance = sqrt(dx * dx + dy * dy + dz * dz);
-                if (distance > 0)
-                {
-                    std::vector<double> direction = {dx / distance, dy / distance, dz / distance};
-                    double Gforce = (G * obj.m_mass * obj2.m_mass) / (distance * distance);
-                    double acc1 = Gforce / obj.m_mass;
-                    std::vector<double> acc = {direction[0] * acc1, direction[1] * acc1, direction[2] * acc1};
-
-                    if (m_gravity)
-                    {
-                        obj.m_velocity.x += static_cast<float>(acc[0]);
-                        obj.m_velocity.y += static_cast<float>(acc[1]);
-                        obj.m_velocity.z += static_cast<float>(acc[2]);
-
-                        obj.m_pos_radius.x += static_cast<float>(obj.m_velocity.x);
-                        obj.m_pos_radius.y += static_cast<float>(obj.m_velocity.y);
-                        obj.m_pos_radius.z += static_cast<float>(obj.m_velocity.z);
-                    }
-                }
-            }
-        }
-    }
-
-    auto Engine::render_scene() -> void
-    {
-        RenderCommand::clear();
-        m_shader_program->bind();
-        m_quad_vao->bind();
-        m_texture->bind(0);
-        RenderCommand::draw_arrays(6);
-    }
-
-    auto Engine::create_compute_program(const char* path) -> Ref<Shader>
-    {
-        std::ifstream in(path);
-        if(!in.is_open())
-        {
-            std::cerr << "Failed to open compute shader: " << path << "\n";
-            return nullptr;
-        }
-        std::stringstream ss;
-        ss << in.rdbuf();
-        std::string src_str = ss.str();
-        return Ref<Shader>(Shader::create_compute("ComputeShader", src_str));
-    }
-
-    auto Engine::QuadVAO() -> std::pair<Ref<VertexArray>, Ref<Texture2D>>
-    {
-        float quad_vertices[] =
-        {
-            // Positions   // TexCoords
-            -1.0f,  1.0f,  0.0f, 1.0f,
-            -1.0f, -1.0f,  0.0f, 0.0f,
-             1.0f, -1.0f,  1.0f, 0.0f,
-            -1.0f,  1.0f,  0.0f, 1.0f,
-             1.0f, -1.0f,  1.0f, 0.0f,
-             1.0f,  1.0f,  1.0f, 1.0f
-        };
-
-        auto vertex_buffer = Ref<VertexBuffer>(VertexBuffer::create(quad_vertices, static_cast<uint32_t>(sizeof(quad_vertices))));
-        VertexBufferLayout layout;
-        layout.push<float>(2); // Position (x, y)
-        layout.push<float>(2); // TexCoord (u, v)
-        vertex_buffer->set_layout(layout);
-
-        auto vertex_array = Ref<VertexArray>(VertexArray::create());
-        vertex_array->add_vertex_buffer(vertex_buffer);
-        auto texture = Texture2D::create(get_compute_width(), m_compute_height);
-
-        return { vertex_array, texture };
-    }
-
-    auto Engine::load_objects_from_scene(const std::vector<Donut::Object>& objects) -> void
-    {
-        m_objects.clear();
-        m_objects.push_back(
-        {
-            glm::vec4(0.00f, 0.00f, 0.00f, m_sag_a.m_rs),
-            glm::vec4(0, 0, 0, 1),
-            static_cast<float>(m_sag_a.m_mass)
-        });
-
-        for (const auto& obj : objects)
-        {
-            ObjectData engine_obj;
-
-            float scale_factor = 1e10f;
-            engine_obj.m_pos_radius = glm::vec4
-            (
-                obj.m_centre.x * scale_factor,
-                obj.m_centre.y * scale_factor,
-                obj.m_centre.z * scale_factor,
-                obj.m_radius * scale_factor
-            );
-
-            engine_obj.m_color = glm::vec4(obj.m_material.m_color, 1.0f);
-
-            float volume  = (4.0f / 3.0f) * 3.14159f * engine_obj.m_pos_radius.w * engine_obj.m_pos_radius.w * engine_obj.m_pos_radius.w;
-            float density = 1e12f;
-            engine_obj.m_mass     = volume * density;
-            engine_obj.m_velocity = glm::vec3(0.0f, 0.0f, 0.0f);
-
-            m_objects.push_back(engine_obj);
-        }
-
-        DONUT_INFO("Loaded {} objects from WorldBuilder scene (scaled up by {})", objects.size(), 1e10f);
-        print_object_info();
-    }
-
-    auto Engine::print_object_info() const -> void
-    {
-        DONUT_INFO("=== Object Information ===");
-        DONUT_INFO("Total objects: {}", m_objects.size());
-
-        for (size_t i = 0; i < m_objects.size(); ++i)
-        {
-            const auto& obj = m_objects[i];
-            DONUT_INFO("Object {}: Pos=({}, {}, {}), Radius={}, Mass={}, Color=({}, {}, {})",
-                i,
-                obj.m_pos_radius.x, obj.m_pos_radius.y, obj.m_pos_radius.z,
-                obj.m_pos_radius.w,
-                obj.m_mass,
-                obj.m_color.x, obj.m_color.y, obj.m_color.z
-            );
-        }
-        DONUT_INFO("Camera position: ({}, {}, {})",
-            m_camera.get_orbital_position().x,
-            m_camera.get_orbital_position().y,
-            m_camera.get_orbital_position().z
-        );
-        DONUT_INFO("Camera radius: {}", m_camera.get_orbital_radius());
-        DONUT_INFO("========================");
-    }
-
-    auto Engine::export_high_res_frame(const std::string& filename, int width, int height) -> void
-    {
-        DONUT_INFO("Exporting high-resolution frame: {}x{} to {}", width, height, filename);
-
-        if (width <= 0 || height <= 0)
-        {
-            DONUT_ERROR("Invalid dimensions for export: {}x{}", width, height);
-            return;
-        }
-
-        if (filename.empty())
-        {
-            DONUT_ERROR("Invalid filename for export");
-            return;
-        }
-
-        int original_width = m_width;
-        int original_height = m_height;
-        int original_compute_height = m_compute_height;
-
-        m_width = width;
-        m_height = height;
-        m_compute_height = height;
-
-        int compute_height = height;
-        int compute_width = (width * compute_height) / height;
-
-        if (compute_width <= 0 || compute_height <= 0)
-        {
-            DONUT_ERROR("Invalid compute dimensions: {}x{}", compute_width, compute_height);
-            return;
-        }
-
-        FramebufferSpecification fb_spec;
-        fb_spec.Width = width;
-        fb_spec.Height = height;
-        fb_spec.attachments = { FramebufferTextureFormat::RGBA8 };
-
-        auto high_res_framebuffer = Framebuffer::create(fb_spec);
-        if (!high_res_framebuffer)
-        {
-            DONUT_ERROR("Failed to create high-resolution framebuffer");
-            return;
-        }
-
-        auto high_res_texture = Texture2D::create(compute_width, compute_height);
-        if (!high_res_texture)
-        {
-            DONUT_ERROR("Failed to create high-resolution texture");
-            return;
-        }
-
-        // Render the geodesic pass into high_res_texture through the geodesic FBO.
-        glBindFramebuffer(GL_FRAMEBUFFER, m_geodesic_fbo);
-        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, high_res_texture->get_renderer_id(), 0);
-        glViewport(0, 0, compute_width, compute_height);
-
-        m_compute_program->bind();
-
-        struct UBOData
-        {
-            glm::vec3 pos;     float _pad0;
-            glm::vec3 right;   float _pad1;
-            glm::vec3 up;      float _pad2;
-            glm::vec3 forward; float _pad3;
-            float tan_half_fov;
-            float aspect;
-            bool  moving;
-            int   _pad4;
-        } data;
-
-        glm::vec3 fwd   = glm::normalize(m_camera.get_orbital_target() - m_camera.get_orbital_position());
-        glm::vec3 up    = glm::vec3(0, 1, 0);
-        glm::vec3 right = glm::normalize(glm::cross(fwd, up));
-        up = glm::cross(right, fwd);
-
-        data.pos        = m_camera.get_orbital_position();
-        data.right      = right;
-        data.up         = up;
-        data.forward    = fwd;
-        data.tan_half_fov = static_cast<float>(tan(glm::radians(60.0f * 0.5f)));
-        data.aspect     = static_cast<float>(compute_width) / static_cast<float>(compute_height);
-        data.moving     = m_camera.is_dragging() || m_camera.is_panning();
-
-        m_camera_ubo->set_data(&data, sizeof(UBOData));
-        m_camera_ubo->bind(1);
-
-        upload_disk_ubo();
-        upload_objects_ubo(m_objects);
-        upload_simulation_ubo();
-        m_compute_program->set_float2("u_Resolution", glm::vec2(static_cast<float>(compute_width), static_cast<float>(compute_height)));
-
-        if (m_hdri_environment)
-        {
-            m_hdri_environment->bind(5);
-            m_compute_program->set_int("u_HDRIEnvironment", 5);
-        }
-
-        draw_geodesic_pass(compute_width, compute_height);
-
-        // Display the rendered frame into the high-res framebuffer for read-back.
-        high_res_framebuffer->bind();
-        RenderCommand::set_viewport(0, 0, width, height);
-        RenderCommand::clear();
-
-        m_shader_program->bind();
-        m_quad_vao->bind();
-
-        high_res_texture->bind(0);
-        m_shader_program->set_int("u_ScreenTexture", 0);
-
-        RenderCommand::disable_depth_test();
-        RenderCommand::draw_arrays(6);
-        RenderCommand::enable_depth_test();
-
-        std::vector<unsigned char> pixels(width * height * 4);
-        DONUT_INFO("Reading {} pixels from framebuffer...", width * height);
-        RenderCommand::read_pixels(0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pixels.data());
-
-        DONUT_INFO("Flipping image vertically...");
-        std::vector<unsigned char> flipped_pixels(width * height * 4);
-        for (int y = 0; y < height; ++y)
-        {
-            for (int x = 0; x < width; ++x)
-            {
-                int src_index = (y * width + x) * 4;
-                int dst_index = ((height - 1 - y) * width + x) * 4;
-                flipped_pixels[dst_index + 0] = pixels[src_index + 0]; // R
-                flipped_pixels[dst_index + 1] = pixels[src_index + 1]; // G
-                flipped_pixels[dst_index + 2] = pixels[src_index + 2]; // B
-                flipped_pixels[dst_index + 3] = pixels[src_index + 3]; // A
-            }
-        }
-
-        DONUT_INFO("Saving PNG file: {}...", filename);
-        int result = stbi_write_png(filename.c_str(), width, height, 4, flipped_pixels.data(), width * 4);
-
-        if (result)
-            DONUT_INFO("Successfully exported high-resolution frame to: {}", filename);
-        else
-            DONUT_ERROR("Failed to export high-resolution frame to: {}", filename);
-
-        high_res_framebuffer->unbind();
-
-        m_width         = original_width;
-        m_height        = original_height;
-        m_compute_height = original_compute_height;
-
-        RenderCommand::set_viewport(0, 0, original_width, original_height);
-    }
-
-}