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|
#include "ui_spike.hpp"
#include "rmlui_renderer_gl3.h"
#include <RmlUi/Core/Context.h>
#include <RmlUi/Core/Core.h>
#include <RmlUi/Core/DataModelHandle.h>
#include <RmlUi/Core/ElementDocument.h>
#include <RmlUi/Core/SystemInterface.h>
// The kernel owns GL; system EGL/GLES headers are allowed here (brief).
// wlr.hpp (via ui_spike.hpp) already pulled <EGL/egl.h>+<EGL/eglext.h>
// through wlr/render/egl.h, and GLES through the adapted renderer; we add
// the dmabuf import entrypoints explicitly.
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <GLES3/gl32.h>
#include <GLES2/gl2ext.h> // glEGLImageTargetTexture2DOES
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <vector>
namespace unbox::kernel {
namespace {
constexpr int kSpikeWidth = 320;
constexpr int kSpikeHeight = 200;
constexpr int kSpikeX = 40; // layout-space origin of the node
constexpr int kSpikeY = 40;
// DRM FourCC for the buffers we allocate / wrap. ARGB8888 is universally
// render+sample-able and matches RMLUi's premultiplied RGBA8 output once
// channel order is accounted for. (FourCC AR24 = little-endian B,G,R,A.)
constexpr std::uint32_t kDrmFormatArgb8888 = 0x34325241; // 'AR24'
// Distinctive solid bands at the document's top and bottom edges. They are
// full-width, unique colors that appear NOWHERE else in the document, so the
// orientation assertion can prove the submitted buffer is upright: the top
// band must land in the TOP rows of the buffer, the bottom band in the
// BOTTOM rows. (A vertical flip would swap them — the bug.)
constexpr int kBandHeight = 12; // px, each band
// Top band #18e0a0 (teal-green); bottom band #e09018 (amber). Stored as the
// RGB byte triplets the Plan-B readback produces (R,G,B order).
constexpr std::uint8_t kTopBandRGB[3] = {0x18, 0xe0, 0xa0};
constexpr std::uint8_t kBottomBandRGB[3] = {0xe0, 0x90, 0x18};
// In-memory hello-world document. Distinctive top/bottom bands (orientation
// proof), a title, a live frame counter via data binding, and a button that
// reacts to hover/click (input proof).
const char* kHelloRml = R"RML(<rml>
<head>
<style>
body { font-family: "Noto Sans"; background: #1e2230; color: #e8ecff;
width: 320px; height: 200px; }
#topband { display: block; width: 320px; height: 12px; background: #18e0a0; }
#bottomband { display: block; width: 320px; height: 12px; background: #e09018;
position: absolute; bottom: 0px; left: 0px; }
h1 { font-size: 22px; margin: 16px; color: #9ecbff; }
p { font-size: 15px; margin: 0 16px 12px 16px; }
button { font-size: 15px; margin: 16px; padding: 8px 16px;
background: #3a4670; color: #ffffff; border-radius: 6px; }
button:hover { background: #5468b0; }
button:active { background: #7e93e0; }
</style>
</head>
<body data-model="spike">
<div id="topband"></div>
<h1>unbox ui spike</h1>
<p>frame {{frame}}</p>
<button>{{label}}</button>
<div id="bottomband"></div>
</body>
</rml>)RML";
// --- SystemInterface: elapsed time + route RmlUi logs to wlr_log ----------
class SpikeSystemInterface final : public Rml::SystemInterface {
public:
auto GetElapsedTime() -> double override {
timespec now{};
clock_gettime(CLOCK_MONOTONIC, &now);
if (start_ == 0.0) {
start_ = static_cast<double>(now.tv_sec) + now.tv_nsec / 1e9;
}
return (static_cast<double>(now.tv_sec) + now.tv_nsec / 1e9) - start_;
}
auto LogMessage(Rml::Log::Type type, const Rml::String& message) -> bool override {
const wlr_log_importance imp = (type == Rml::Log::LT_ERROR || type == Rml::Log::LT_ASSERT)
? WLR_ERROR
: (type == Rml::Log::LT_WARNING ? WLR_INFO : WLR_DEBUG);
wlr_log(imp, "[rmlui] %s", message.c_str());
return true;
}
private:
double start_ = 0.0;
};
// --- A data-ptr wlr_buffer wrapping heap memory (Plan B target) -----------
//
// The wlr GLES2 renderer can sample a WLR_BUFFER_CAP_DATA_PTR buffer (it
// uploads via begin/end_data_ptr_access). Works on both the headless/pixman
// and GPU/gles2 backends, which is why this is the robust spike landing.
struct ShmBuffer {
wlr_buffer base{};
std::vector<std::uint8_t> data;
std::uint32_t format = kDrmFormatArgb8888;
std::size_t stride = 0;
bool dropped = false;
};
void shm_buffer_destroy(wlr_buffer* wlr_buf) {
auto* buf = reinterpret_cast<ShmBuffer*>(wlr_buf);
wlr_buffer_finish(&buf->base);
delete buf;
}
auto shm_buffer_begin_data_ptr_access(wlr_buffer* wlr_buf, std::uint32_t /*flags*/, void** data,
std::uint32_t* format, std::size_t* stride) -> bool {
auto* buf = reinterpret_cast<ShmBuffer*>(wlr_buf);
*data = buf->data.data();
*format = buf->format;
*stride = buf->stride;
return true;
}
void shm_buffer_end_data_ptr_access(wlr_buffer* /*wlr_buf*/) {}
const wlr_buffer_impl kShmBufferImpl = {
.destroy = shm_buffer_destroy,
.get_dmabuf = nullptr,
.get_shm = nullptr,
.begin_data_ptr_access = shm_buffer_begin_data_ptr_access,
.end_data_ptr_access = shm_buffer_end_data_ptr_access,
};
auto make_shm_buffer(int width, int height) -> ShmBuffer* {
auto* buf = new ShmBuffer();
buf->stride = static_cast<std::size_t>(width) * 4;
buf->data.assign(buf->stride * static_cast<std::size_t>(height), 0);
wlr_buffer_init(&buf->base, &kShmBufferImpl, width, height);
return buf;
}
} // namespace
// --- Impl -----------------------------------------------------------------
struct UiSpike::Impl {
EGLDisplay egl_display = EGL_NO_DISPLAY;
EGLContext egl_context = EGL_NO_CONTEXT;
EGLContext saved_context = EGL_NO_CONTEXT;
EGLSurface saved_draw = EGL_NO_SURFACE;
EGLSurface saved_read = EGL_NO_SURFACE;
wlr_allocator* allocator = nullptr; // borrowed (server-owned)
wlr_renderer* renderer = nullptr; // borrowed (server-owned)
// Sibling-context GL objects.
GLuint fbo = 0;
GLuint color_tex = 0;
// Plan A (dmabuf) state — populated only if A engages.
wlr_buffer* dmabuf = nullptr; // the swapchain-acquired render target
EGLImageKHR egl_image = EGL_NO_IMAGE_KHR;
// Plan B (shm copy) state.
ShmBuffer* shm = nullptr;
std::vector<std::uint8_t> readback; // glReadPixels scratch
// RMLUi.
std::unique_ptr<SpikeSystemInterface> system;
std::unique_ptr<RenderInterface_GL3> render_iface;
Rml::Context* context = nullptr; // owned by Rml (RemoveContext)
Rml::ElementDocument* document = nullptr;
Rml::DataModelHandle model;
// Data-bound document state.
int frame = 0;
Rml::String label = "hover me";
// Scene.
wlr_scene_buffer* scene_buffer = nullptr;
Plan plan = Plan::Disabled;
int frame_count = 0;
// EGL extension entrypoints (loaded once).
PFNEGLCREATEIMAGEKHRPROC egl_create_image = nullptr;
PFNEGLDESTROYIMAGEKHRPROC egl_destroy_image = nullptr;
PFNGLEGLIMAGETARGETTEXTURE2DOESPROC gl_image_target_texture = nullptr;
bool make_current() {
saved_context = eglGetCurrentContext();
saved_draw = eglGetCurrentSurface(EGL_DRAW);
saved_read = eglGetCurrentSurface(EGL_READ);
return eglMakeCurrent(egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE, egl_context) == EGL_TRUE;
}
void restore_current() {
eglMakeCurrent(egl_display, saved_draw, saved_read, saved_context);
}
bool init(wlr_scene_tree* parent, EGLDisplay display, wlr_allocator* alloc,
wlr_renderer* rend);
bool try_plan_a();
void setup_plan_b();
void render_locked();
void teardown();
};
bool UiSpike::Impl::init(wlr_scene_tree* parent, EGLDisplay display, wlr_allocator* alloc,
wlr_renderer* rend) {
egl_display = display;
allocator = alloc;
renderer = rend;
// 1. Sibling GLES 3.2 context sharing the wlr EGLDisplay. No GL object
// sharing — buffers cross via dmabuf/EGLImage or CPU copy only, so we
// do NOT pass the wlr context as share_context.
if (eglBindAPI(EGL_OPENGL_ES_API) != EGL_TRUE) {
wlr_log(WLR_ERROR, "ui-spike: eglBindAPI(ES) failed");
return false;
}
const EGLint config_attribs[] = {
EGL_SURFACE_TYPE, EGL_PBUFFER_BIT, EGL_RENDERABLE_TYPE, EGL_OPENGL_ES3_BIT,
EGL_RED_SIZE, 8, EGL_GREEN_SIZE, 8, EGL_BLUE_SIZE, 8, EGL_ALPHA_SIZE, 8,
EGL_NONE,
};
EGLConfig config = nullptr;
EGLint num_config = 0;
if (eglChooseConfig(egl_display, config_attribs, &config, 1, &num_config) != EGL_TRUE ||
num_config < 1) {
wlr_log(WLR_ERROR, "ui-spike: eglChooseConfig found no ES3 config");
return false;
}
const EGLint ctx_attribs[] = {
EGL_CONTEXT_MAJOR_VERSION, 3, EGL_CONTEXT_MINOR_VERSION, 2, EGL_NONE,
};
egl_context = eglCreateContext(egl_display, config, EGL_NO_CONTEXT, ctx_attribs);
if (egl_context == EGL_NO_CONTEXT) {
wlr_log(WLR_ERROR, "ui-spike: eglCreateContext(ES 3.2) failed (0x%x)", eglGetError());
return false;
}
if (!make_current()) {
wlr_log(WLR_ERROR, "ui-spike: eglMakeCurrent (surfaceless) failed (0x%x)", eglGetError());
restore_current();
return false;
}
// Load EGLImage entrypoints for the Plan-A attempt.
egl_create_image =
reinterpret_cast<PFNEGLCREATEIMAGEKHRPROC>(eglGetProcAddress("eglCreateImageKHR"));
egl_destroy_image =
reinterpret_cast<PFNEGLDESTROYIMAGEKHRPROC>(eglGetProcAddress("eglDestroyImageKHR"));
gl_image_target_texture = reinterpret_cast<PFNGLEGLIMAGETARGETTEXTURE2DOESPROC>(
eglGetProcAddress("glEGLImageTargetTexture2DOES"));
// 2. RMLUi render interface (our GLES3-adapted GL3 backend).
Rml::String gl_msg;
if (!RmlGL3::Initialize(&gl_msg)) {
wlr_log(WLR_ERROR, "ui-spike: RmlGL3::Initialize failed");
restore_current();
return false;
}
wlr_log(WLR_INFO, "ui-spike: %s", gl_msg.c_str());
render_iface = std::make_unique<RenderInterface_GL3>();
if (!*render_iface) {
wlr_log(WLR_ERROR, "ui-spike: RenderInterface_GL3 construction failed");
restore_current();
return false;
}
render_iface->SetViewport(kSpikeWidth, kSpikeHeight);
// 3. Offscreen FBO + color target. Plan A first, Plan B on any failure.
glGenFramebuffers(1, &fbo);
if (!try_plan_a()) {
setup_plan_b();
}
// flip_y: the FBO color attachment (dmabuf in Plan A, GL texture read
// back in Plan B) is sampled/scanned-out row 0 = top, but GL renders with
// a bottom-left origin. Flip the final composite so the submitted buffer
// is upright; display then matches document coords, so pointer input is
// forwarded unflipped (on-screen button == document button).
render_iface->SetOutputFramebuffer(fbo, /*flip_y=*/true);
// Verify the FBO is complete before committing to RMLUi init.
glBindFramebuffer(GL_FRAMEBUFFER, fbo);
const GLenum fb_status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
if (fb_status != GL_FRAMEBUFFER_COMPLETE) {
wlr_log(WLR_ERROR, "ui-spike: output FBO incomplete (0x%x)", fb_status);
restore_current();
return false;
}
// 4. RMLUi core + font + context + document.
system = std::make_unique<SpikeSystemInterface>();
Rml::SetSystemInterface(system.get());
Rml::SetRenderInterface(render_iface.get());
if (!Rml::Initialise()) {
wlr_log(WLR_ERROR, "ui-spike: Rml::Initialise failed");
restore_current();
return false;
}
if (!Rml::LoadFontFace("/usr/share/fonts/noto/NotoSans-Regular.ttf")) {
wlr_log(WLR_INFO, "ui-spike: NotoSans not found; disabling spike gracefully");
Rml::Shutdown();
restore_current();
return false;
}
context = Rml::CreateContext("spike", Rml::Vector2i(kSpikeWidth, kSpikeHeight));
if (context == nullptr) {
wlr_log(WLR_ERROR, "ui-spike: CreateContext failed");
Rml::Shutdown();
restore_current();
return false;
}
if (Rml::DataModelConstructor ctor = context->CreateDataModel("spike")) {
ctor.Bind("frame", &frame);
ctor.Bind("label", &label);
model = ctor.GetModelHandle();
}
document = context->LoadDocumentFromMemory(kHelloRml);
if (document == nullptr) {
wlr_log(WLR_ERROR, "ui-spike: LoadDocumentFromMemory failed");
Rml::Shutdown();
restore_current();
return false;
}
document->Show();
// 5. Scene node. Start with a transparent/empty buffer; tick() fills it.
scene_buffer = wlr_scene_buffer_create(parent, nullptr);
if (scene_buffer == nullptr) {
wlr_log(WLR_ERROR, "ui-spike: wlr_scene_buffer_create failed");
Rml::Shutdown();
restore_current();
return false;
}
wlr_scene_node_set_position(&scene_buffer->node, kSpikeX, kSpikeY);
restore_current();
wlr_log(WLR_INFO, "ui-spike: bridge up (plan %s, %dx%d)",
plan == Plan::Dmabuf ? "A/dmabuf" : "B/shm-copy", kSpikeWidth, kSpikeHeight);
return true;
}
// Plan A: allocate a dmabuf wlr_buffer via the server allocator, import it
// into the sibling context as an EGLImage, bind that as the FBO color
// attachment. Returns false (cleaning up) on any failure so init() falls to B.
bool UiSpike::Impl::try_plan_a() {
// Spike instrumentation: force the Plan-B fallback for testing the CPU
// copy path even on hardware where Plan A works. Harmless in production.
if (std::getenv("UNBOX_UI_SPIKE_FORCE_SHM") != nullptr) {
wlr_log(WLR_INFO, "ui-spike: plan A skipped — UNBOX_UI_SPIKE_FORCE_SHM set");
return false;
}
if ((allocator->buffer_caps & WLR_BUFFER_CAP_DMABUF) == 0) {
wlr_log(WLR_INFO, "ui-spike: plan A skipped — allocator has no DMABUF cap");
return false;
}
if (egl_create_image == nullptr || gl_image_target_texture == nullptr) {
wlr_log(WLR_INFO, "ui-spike: plan A skipped — no EGLImage dmabuf-import entrypoints");
return false;
}
const char* exts = eglQueryString(egl_display, EGL_EXTENSIONS);
if (exts == nullptr || std::strstr(exts, "EGL_EXT_image_dma_buf_import") == nullptr) {
wlr_log(WLR_INFO, "ui-spike: plan A skipped — no EGL_EXT_image_dma_buf_import");
return false;
}
// Allocate one dmabuf via the allocator using a LINEAR/INVALID modifier
// list (legacy-driver-safe; crocus is fine with linear).
wlr_drm_format fmt{};
fmt.format = kDrmFormatArgb8888;
const std::uint64_t modifiers[] = {0 /* DRM_FORMAT_MOD_LINEAR */};
fmt.len = 1;
fmt.capacity = 1;
fmt.modifiers = const_cast<std::uint64_t*>(modifiers);
wlr_buffer* buf = wlr_allocator_create_buffer(allocator, kSpikeWidth, kSpikeHeight, &fmt);
if (buf == nullptr) {
wlr_log(WLR_INFO, "ui-spike: plan A — allocator could not create dmabuf");
return false;
}
wlr_dmabuf_attributes attribs{};
if (!wlr_buffer_get_dmabuf(buf, &attribs) || attribs.n_planes < 1) {
wlr_log(WLR_INFO, "ui-spike: plan A — buffer has no dmabuf attrs");
wlr_buffer_drop(buf);
return false;
}
// Build the EGLImage from the dmabuf (single-plane fast path).
EGLint img_attribs[] = {
EGL_WIDTH, attribs.width,
EGL_HEIGHT, attribs.height,
EGL_LINUX_DRM_FOURCC_EXT, static_cast<EGLint>(attribs.format),
EGL_DMA_BUF_PLANE0_FD_EXT, attribs.fd[0],
EGL_DMA_BUF_PLANE0_OFFSET_EXT, static_cast<EGLint>(attribs.offset[0]),
EGL_DMA_BUF_PLANE0_PITCH_EXT, static_cast<EGLint>(attribs.stride[0]),
EGL_NONE,
};
egl_image = egl_create_image(egl_display, EGL_NO_CONTEXT, EGL_LINUX_DMA_BUF_EXT,
static_cast<EGLClientBuffer>(nullptr), img_attribs);
if (egl_image == EGL_NO_IMAGE_KHR) {
wlr_log(WLR_INFO, "ui-spike: plan A — eglCreateImageKHR failed (0x%x)", eglGetError());
wlr_buffer_drop(buf);
return false;
}
glGenTextures(1, &color_tex);
glBindTexture(GL_TEXTURE_2D, color_tex);
gl_image_target_texture(GL_TEXTURE_2D, static_cast<GLeglImageOES>(egl_image));
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindFramebuffer(GL_FRAMEBUFFER, fbo);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, color_tex, 0);
const GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
if (status != GL_FRAMEBUFFER_COMPLETE) {
wlr_log(WLR_INFO, "ui-spike: plan A — FBO from EGLImage incomplete (0x%x)", status);
egl_destroy_image(egl_display, egl_image);
egl_image = EGL_NO_IMAGE_KHR;
glDeleteTextures(1, &color_tex);
color_tex = 0;
wlr_buffer_drop(buf);
return false;
}
dmabuf = buf;
plan = Plan::Dmabuf;
wlr_log(WLR_INFO, "ui-spike: plan A engaged (dmabuf-backed FBO)");
return true;
}
// Plan B: a plain GL texture color attachment; results read back to a
// data-ptr wlr_buffer with glReadPixels each frame.
void UiSpike::Impl::setup_plan_b() {
glGenTextures(1, &color_tex);
glBindTexture(GL_TEXTURE_2D, color_tex);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, kSpikeWidth, kSpikeHeight, 0, GL_RGBA,
GL_UNSIGNED_BYTE, nullptr);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindFramebuffer(GL_FRAMEBUFFER, fbo);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, color_tex, 0);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
shm = make_shm_buffer(kSpikeWidth, kSpikeHeight);
readback.assign(static_cast<std::size_t>(kSpikeWidth) * kSpikeHeight * 4, 0);
plan = Plan::ShmCopy;
wlr_log(WLR_INFO, "ui-spike: plan B engaged (FBO + glReadPixels -> shm)");
}
// Render one dirty frame. Caller holds the sibling context current.
void UiSpike::Impl::render_locked() {
// Tick the bound state; dirtying drives the repeated render proof.
frame += 1;
if (model) {
model.DirtyVariable("frame");
}
context->Update();
render_iface->BeginFrame();
render_iface->Clear();
context->Render();
render_iface->EndFrame(); // composites into `fbo` (SetOutputFramebuffer)
if (plan == Plan::Dmabuf) {
// The wlr renderer will sample the dmabuf directly; ensure all GL
// writes have landed before the compositor reads it. A spike uses
// glFinish; the real substrate will use an EGL fence.
glFinish();
wlr_scene_buffer_set_buffer(scene_buffer, dmabuf);
} else {
// Plan B: read the FBO back into the data-ptr buffer.
glBindFramebuffer(GL_FRAMEBUFFER, fbo);
glReadPixels(0, 0, kSpikeWidth, kSpikeHeight, GL_RGBA, GL_UNSIGNED_BYTE, readback.data());
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// RMLUi outputs premultiplied RGBA8 (R,G,B,A byte order). The shm
// buffer is FourCC AR24 = little-endian {B,G,R,A}. Swap R<->B; the
// result is already premultiplied which wlroots expects.
const std::size_t px = static_cast<std::size_t>(kSpikeWidth) * kSpikeHeight;
std::uint8_t* dst = shm->data.data();
const std::uint8_t* src = readback.data();
for (std::size_t i = 0; i < px; ++i) {
dst[i * 4 + 0] = src[i * 4 + 2]; // B
dst[i * 4 + 1] = src[i * 4 + 1]; // G
dst[i * 4 + 2] = src[i * 4 + 0]; // R
dst[i * 4 + 3] = src[i * 4 + 3]; // A
}
wlr_scene_buffer_set_buffer(scene_buffer, &shm->base);
}
frame_count += 1;
}
void UiSpike::Impl::teardown() {
// RMLUi teardown needs the sibling context current (GL deletes).
const bool ok = make_current();
if (scene_buffer != nullptr) {
wlr_scene_node_destroy(&scene_buffer->node);
scene_buffer = nullptr;
}
if (context != nullptr) {
// Document is owned by the context; Shutdown tears everything down.
Rml::Shutdown();
context = nullptr;
document = nullptr;
}
render_iface.reset();
if (color_tex != 0) {
glDeleteTextures(1, &color_tex);
color_tex = 0;
}
if (fbo != 0) {
glDeleteFramebuffers(1, &fbo);
fbo = 0;
}
if (egl_image != EGL_NO_IMAGE_KHR && egl_destroy_image != nullptr) {
egl_destroy_image(egl_display, egl_image);
egl_image = EGL_NO_IMAGE_KHR;
}
if (dmabuf != nullptr) {
wlr_buffer_drop(dmabuf);
dmabuf = nullptr;
}
if (shm != nullptr) {
wlr_buffer_drop(&shm->base); // triggers shm_buffer_destroy -> delete
shm = nullptr;
}
if (ok) {
restore_current();
}
if (egl_context != EGL_NO_CONTEXT) {
eglDestroyContext(egl_display, egl_context);
egl_context = EGL_NO_CONTEXT;
}
}
// --- UiSpike (public-ish private surface) ---------------------------------
auto UiSpike::create(wlr_scene_tree* parent, EGLDisplay egl_display, wlr_allocator* allocator,
wlr_renderer* renderer) -> std::unique_ptr<UiSpike> {
auto impl = std::make_unique<Impl>();
if (!impl->init(parent, egl_display, allocator, renderer)) {
impl->teardown(); // safe to call after partial init
// Hand back a Disabled bridge (never throws, never aborts the server).
auto disabled = std::make_unique<Impl>();
disabled->plan = Plan::Disabled;
return std::unique_ptr<UiSpike>(new UiSpike(std::move(disabled)));
}
return std::unique_ptr<UiSpike>(new UiSpike(std::move(impl)));
}
UiSpike::UiSpike(std::unique_ptr<Impl> impl) : impl_(std::move(impl)) {}
UiSpike::~UiSpike() {
if (impl_->plan != Plan::Disabled) {
impl_->teardown();
}
}
void UiSpike::tick() {
if (impl_->plan == Plan::Disabled) {
return;
}
// Render every tick (spike fidelity: the frame counter dirties the doc
// each call, so the context is always dirty — proving repeated cycles).
if (!impl_->make_current()) {
return;
}
impl_->render_locked();
impl_->restore_current();
}
void UiSpike::on_pointer_motion(double sx, double sy) {
if (impl_->plan == Plan::Disabled || impl_->context == nullptr) {
return;
}
impl_->context->ProcessMouseMove(static_cast<int>(sx), static_cast<int>(sy), 0);
}
void UiSpike::on_pointer_button(bool pressed) {
if (impl_->plan == Plan::Disabled || impl_->context == nullptr) {
return;
}
if (pressed) {
impl_->context->ProcessMouseButtonDown(0, 0);
} else {
impl_->context->ProcessMouseButtonUp(0, 0);
}
}
auto UiSpike::node() const -> wlr_scene_node* {
return impl_->scene_buffer != nullptr ? &impl_->scene_buffer->node : nullptr;
}
auto UiSpike::plan() const -> Plan {
return impl_->plan;
}
auto UiSpike::frame_count() const -> int {
return impl_->frame_count;
}
auto UiSpike::check_orientation() const -> int {
// Only the shm path keeps a CPU readback to inspect, and only after a
// frame has been submitted.
if (impl_->plan != Plan::ShmCopy || impl_->frame_count == 0) {
return 0;
}
const std::uint8_t* px = impl_->readback.data(); // R,G,B,A, row 0 = top
const int w = kSpikeWidth;
const int h = kSpikeHeight;
auto matches = [](const std::uint8_t* p, const std::uint8_t (&c)[3]) {
const int dr = static_cast<int>(p[0]) - c[0];
const int dg = static_cast<int>(p[1]) - c[1];
const int db = static_cast<int>(p[2]) - c[2];
return dr * dr + dg * dg + db * db < 24 * 24; // tolerant of AA edges
};
// Count band pixels in the top kBandHeight rows vs the bottom kBandHeight
// rows, sampling the full width. Upright => top band dominates the top
// rows and bottom band the bottom rows; a flip swaps them.
int top_band_in_top = 0;
int top_band_in_bottom = 0;
int bottom_band_in_top = 0;
int bottom_band_in_bottom = 0;
for (int row = 0; row < kBandHeight; ++row) {
const int top_row = row;
const int bot_row = h - 1 - row;
for (int x = 0; x < w; ++x) {
const std::uint8_t* pt = px + (static_cast<std::size_t>(top_row) * w + x) * 4;
const std::uint8_t* pb = px + (static_cast<std::size_t>(bot_row) * w + x) * 4;
if (matches(pt, kTopBandRGB)) {
++top_band_in_top;
}
if (matches(pb, kTopBandRGB)) {
++top_band_in_bottom;
}
if (matches(pt, kBottomBandRGB)) {
++bottom_band_in_top;
}
if (matches(pb, kBottomBandRGB)) {
++bottom_band_in_bottom;
}
}
}
// Need a clear, unambiguous signal in one orientation.
const bool upright = top_band_in_top > 100 && bottom_band_in_bottom > 100 &&
top_band_in_top > top_band_in_bottom &&
bottom_band_in_bottom > bottom_band_in_top;
const bool flipped = top_band_in_bottom > 100 && bottom_band_in_top > 100 &&
top_band_in_bottom > top_band_in_top &&
bottom_band_in_top > bottom_band_in_bottom;
if (upright) {
return 1;
}
if (flipped) {
return -1;
}
return 0;
}
} // namespace unbox::kernel
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