chore: capture tool and dev env hooks

1 files changed, 58 insertions, 0 deletions

diff --git a/src/core/application.cpp b/src/core/application.cpp
index d04cde8..e02edb6 100644
--- a/src/core/application.cpp
+++ b/src/core/application.cpp
@@ -9,7 +9,12 @@
 
 #include <glad/gl.h>
 
+#include <algorithm>
+#include <charconv>
 #include <chrono>
+#include <cstdlib>
+#include <fstream>
+#include <vector>
 
 namespace Hsdbg
 {
@@ -19,6 +24,38 @@ namespace Hsdbg
 
         constexpr float MAX_DELTA_TIME = 0.25f;
         constexpr double MINIMIZED_WAIT_TIMEOUT = 0.1;
+
+        auto capture_frame(uint64_t frame, uint32_t width, uint32_t height) -> bool
+        {
+            static const char* path = std::getenv("HSDBG_CAPTURE");
+            if (path == nullptr)
+                return false;
+
+            static const uint64_t target = [] {
+                uint64_t value = 240;
+                if (const char* text = std::getenv("HSDBG_CAPTURE_FRAME"))
+                    std::from_chars(text, text + std::char_traits<char>::length(text), value);
+                return value;
+            }();
+
+            if (frame != target)
+                return false;
+
+            const size_t stride = static_cast<size_t>(width) * 3;
+            std::vector<unsigned char> pixels(stride * height);
+            glPixelStorei(GL_PACK_ALIGNMENT, 1);
+            glReadPixels(0, 0, static_cast<GLsizei>(width), static_cast<GLsizei>(height),
+                         GL_RGB, GL_UNSIGNED_BYTE, pixels.data());
+
+            std::ofstream out(path, std::ios::binary);
+            out << "P6\n" << width << ' ' << height << "\n255\n";
+            for (uint32_t y = height; y-- > 0;)
+                out.write(reinterpret_cast<const char*>(pixels.data() + y * stride),
+                          static_cast<std::streamsize>(stride));
+
+            Log::info("capture: wrote '{}' ({}x{})", path, width, height);
+            return true;
+        }
     }
 
     Application* Application::s_instance = nullptr;
@@ -109,6 +146,24 @@ namespace Hsdbg
     auto Application::update() -> void
     {
         m_debugger->update();
+
+        static const std::vector<uint64_t> step_frames = [] {
+            std::vector<uint64_t> frames;
+            const char* text = std::getenv("HSDBG_STEP_AT");
+            for (const char* at = text; at != nullptr && *at != '\0';)
+            {
+                uint64_t value = 0;
+                const auto [next, error] = std::from_chars(at, at + std::char_traits<char>::length(at), value);
+                if (error != std::errc{})
+                    break;
+                frames.push_back(value);
+                at = *next == ',' ? next + 1 : next;
+            }
+            return frames;
+        }();
+
+        if (std::ranges::find(step_frames, m_frame_count) != step_frames.end() && m_debugger->is_stopped())
+            (void)m_debugger->step_over();
     }
 
     auto Application::render() -> void
@@ -123,5 +178,8 @@ namespace Hsdbg
         m_ui->begin_frame();
         m_ui->draw(*m_debugger);
         m_ui->end_frame();
+
+        if (capture_frame(m_frame_count, m_window->framebuffer_width(), m_window->framebuffer_height()))
+            close();
     }
 }