CoopAllTheThings/host/src/capture_panel.cpp

#include "capture_panel.hpp"

#include <cstdio>

#include "imgui.h"
#include "injection_panel.hpp"

namespace coop
{

namespace
{
const ImVec4 kGreen(0.4f, 1.0f, 0.4f, 1.0f);
const ImVec4 kRed(1.0f, 0.45f, 0.4f, 1.0f);
} // namespace

bool CapturePanel::init(ID3D11Device* device)
{
	device_ = device;
	shared_.init(device); // best effort; the Hooked source is unavailable if it fails
	return renderer_.init(device);
}

void CapturePanel::draw_ui(const FrameStats& stats)
{
	ImGui::SetNextWindowPos(ImVec2(460, 40), ImGuiCond_FirstUseEver);
	ImGui::SetNextWindowSize(ImVec2(360, 0), ImGuiCond_FirstUseEver);
	ImGui::Begin("Video mirror");

	const unsigned long hook_pid = injection_ != nullptr ? injection_->target_pid() : 0;
	const bool have_wgc_target = target_ != nullptr && IsWindow(target_);
	const bool have_hook = hook_pid != 0;
	const bool have_source = source_ == Source_Hooked ? have_hook : have_wgc_target;

	ImGui::BeginDisabled(!have_source);
	if (ImGui::Checkbox("Mirror game window", &enabled_) && !enabled_)
	{
		capture_.stop();
		shared_.reset();
		if (injection_ != nullptr)
		{
			injection_->request_video(false); // stop the in-game Present hook
		}
	}
	ImGui::EndDisabled();

	// Source selector. Switching tears down the other source and (un)installs the
	// Present hook so the game only pays for the path actually in use.
	ImGui::TextUnformatted("Source:");
	ImGui::SameLine();
	int prev_source = source_;
	ImGui::RadioButton("WGC", &source_, Source_Wgc);
	ImGui::SameLine();
	ImGui::RadioButton("Hooked (Present)", &source_, Source_Hooked);
	if (source_ != prev_source)
	{
		capture_.stop();
		shared_.reset();
		if (injection_ != nullptr)
		{
			injection_->request_video(enabled_ && source_ == Source_Hooked);
		}
	}

	if (!have_source)
	{
		ImGui::TextDisabled(source_ == Source_Hooked
		                        ? "Inject into a game first (the Present hook is the source)."
		                        : "Inject into a game first (its window is the source).");
	}

	if (source_ == Source_Wgc)
	{
		// Start/restart WGC capture when enabled and the target window changes.
		if (enabled_ && have_wgc_target && capture_.target() != target_)
		{
			if (!capture_.start(target_, device_))
			{
				enabled_ = false;
				ImGui::TextColored(kRed, "Failed to start capture.");
			}
		}
		if (capture_.running())
		{
			ImGui::TextColored(kGreen, "Capturing %ux%u (WGC)", capture_.frame_width(), capture_.frame_height());
		}
	}
	else // Source_Hooked
	{
		if (enabled_ && injection_ != nullptr)
		{
			// Keep the subsystem requested (a fresh inject may have reset control).
			if (!injection_->video_requested())
			{
				injection_->request_video(true);
			}
			const VideoShareView share = injection_->video_share();
			if (shared_.frames_copied() > 0 && shared_.width() > 0)
			{
				ImGui::TextColored(kGreen, "Mirroring %ux%u (hooked, %llu frames)", shared_.width(),
				                   shared_.height(), static_cast<unsigned long long>(shared_.frames_copied()));
			}
			else if (share.present_calls > 0)
			{
				ImGui::TextColored(kGreen, "Present hooked (%llu calls); opening shared texture...",
				                   static_cast<unsigned long long>(share.present_calls));
			}
			else
			{
				ImGui::TextDisabled("Waiting for hooked frames (the game may not render via DXGI).");
			}
		}
	}

	draw_perf_graphs(stats);

	ImGui::End();
}

void CapturePanel::draw_perf_graphs(const FrameStats& stats)
{
	// The mirror renders into this window, so the host's render frame timing is
	// the mirror's performance. Plot the recent history and summarise it.
	ImGui::SeparatorText("Render performance");

	float ms[FrameStats::kHistory] = {};
	const int n = stats.copy_frame_ms(ms);
	if (n == 0)
	{
		ImGui::TextDisabled("Gathering samples...");
		return;
	}

	float fps[FrameStats::kHistory] = {};
	for (int i = 0; i < n; ++i)
	{
		fps[i] = ms[i] > 0.0f ? 1000.0f / ms[i] : 0.0f;
	}

	float min_ms = 0.0f, max_ms = 0.0f, avg_ms = 0.0f;
	stats.history_stats(min_ms, max_ms, avg_ms);
	const float avg_fps = avg_ms > 0.0f ? 1000.0f / avg_ms : 0.0f;
	const float min_fps = max_ms > 0.0f ? 1000.0f / max_ms : 0.0f; // slowest frame -> lowest FPS
	const float max_fps = min_ms > 0.0f ? 1000.0f / min_ms : 0.0f;

	char overlay[64];
	std::snprintf(overlay, sizeof(overlay), "avg %.2f ms", avg_ms);
	// Fixed 0..33 ms scale (30 FPS floor) so the line height is meaningful frame
	// to frame rather than auto-rescaling.
	ImGui::PlotLines("##frametime", ms, n, 0, overlay, 0.0f, 33.0f, ImVec2(-1.0f, 60.0f));
	ImGui::Text("Frametime  avg %.2f  min %.2f  max %.2f ms", avg_ms, min_ms, max_ms);

	std::snprintf(overlay, sizeof(overlay), "avg %.0f FPS", avg_fps);
	ImGui::PlotLines("##fps", fps, n, 0, overlay, 0.0f, 144.0f, ImVec2(-1.0f, 60.0f));
	ImGui::Text("FPS        avg %.0f  min %.0f  max %.0f", avg_fps, min_fps, max_fps);
}

void CapturePanel::render(ID3D11DeviceContext* ctx, std::uint32_t dst_w, std::uint32_t dst_h)
{
	if (!enabled_)
	{
		return;
	}
	if (source_ == Source_Hooked)
	{
		if (injection_ == nullptr)
		{
			return;
		}
		if (shared_.update(injection_->video_share(), injection_->target_pid()) && shared_.srv() != nullptr)
		{
			renderer_.draw(ctx, shared_.srv(), shared_.width(), shared_.height(), dst_w, dst_h);
		}
	}
	else if (capture_.running())
	{
		capture_.draw_latest(renderer_, ctx, dst_w, dst_h);
	}
}

} // namespace coop