hypr-chrome/src/ChromePassElement.cpp

#include "ChromePassElement.hpp"
#include "Globals.hpp"
#include "ChromeDecoration.hpp"
#include "ChromeDecorationGeometry.hpp"

#include <hyprland/src/Compositor.hpp>
#include <hyprland/src/desktop/view/Window.hpp>
#include <hyprland/src/render/Renderer.hpp>
#include <hyprland/src/render/Texture.hpp>
#include <hyprland/src/render/pass/TexPassElement.hpp>

ChromePassElement::ChromePassElement(const SData& data_) : data(data_) {}

std::vector<UP<IPassElement>> ChromePassElement::draw() {
  const auto monitor = g_pHyprRenderer->m_renderData.pMonitor.lock();
  if (!monitor)
    return {};

  const auto window = data.decoration->GetOwner();
  if (!window)
    return {};

  auto box = data.decoration->FullDecorationExtentGlobal();
  box.translate(-monitor->m_position).scale(monitor->m_scale);

  // Round the position and the size independently, rather than via
  // CBox::round(). That derives the size from the two *rounded corners*
  // (round(x + w) - round(x)), which makes it a function of the position's
  // fractional part - so a box that is merely sliding, at a perfectly
  // constant size, has its rounded w/h flip by a pixel every few frames.
  // Every one of those flips misses the caches in GetBorderTexture /
  // GetShadowTexture / GetTitleTexture, each miss being a full cairo
  // re-render plus a GPU re-upload of a texture that didn't actually change
  // appearance - which is precisely what a workspace switch, a window move,
  // or any other position-only animation does, every frame, for every window
  // on screen. Rounded on its own, the size stays a pure function of the
  // window's own size and can't be perturbed by translation at all.
  //
  // What round()'s coupling buys is a far edge that lands on the same device
  // pixel as an adjacent box's near edge. Nothing abuts this box - it's a
  // free-floating decoration drawn over everything - so there is no seam here
  // to keep closed.
  box = CBox{box.pos().round(), box.size().round()};

  if (box.w < 1 || box.h < 1)
    return {};

  // Chamfer amount is inferred from the window's own border rounding, in
  // device pixels, so the frame's cut corners track the window's rounding
  // live (config reload, per-window rules, animations).
  const float chamferPx = window->rounding() * monitor->m_scale;
  const float extentPx = static_cast<float>(PluginState->config.extent->value()) * monitor->m_scale;
  const bool isActive = g_pCompositor->isWindowActive(window);
  // When follow_hyprland_border_color is set, track Hyprland's own
  // general:col.active_border / col.inactive_border (already resolved per
  // focus state and animated by the compositor), stops and angle included.
  // Otherwise (or if Hyprland reports no border color at all) fall back to
  // our own active_color/inactive_color config, which take the same
  // gradient syntax.
  const auto& hyprlandBorder = window->m_realBorderColor;
  const bool followHyprlandColor = PluginState->config.followHyprlandBorderColor->value() && !hyprlandBorder.m_colors.empty();
  const auto gradient = ChromeGradient::From(followHyprlandColor
    ? hyprlandBorder
    : (isActive ? PluginState->config.activeColor->value() : PluginState->config.inactiveColor->value()));
  const float borderAlpha = gradient.FirstAlpha();
  const float glowPx = static_cast<float>(PluginState->config.glowSize->value()) * monitor->m_scale;
  const float glowStrength = static_cast<float>(PluginState->config.glowStrength->value());
  const float titleBarHeightPx = static_cast<float>(PluginState->config.titlebarHeight->value()) * monitor->m_scale;
  const float textSizePx = static_cast<float>(PluginState->config.titlebarTextSize->value()) * monitor->m_scale;
  const std::string fontFamily = PluginState->config.titlebarFont->value();

  // Base geometry (everything but the title bar plateau's own width - that
  // depends on the rendered title text, which can only be measured by
  // actually rendering it). MaxTitleBarWidth() bounds that render so a long
  // title gets ellipsized rather than growing the plateau into the
  // self-intersection GetBorderTexture's cairo path would otherwise risk.
  const auto baseGeo = ChromeDecorationGeometry::ComputeBase({box.w, box.h}, extentPx, chamferPx, titleBarHeightPx);
  // Padding around the title text, inside the plateau.
  const float titlePadding = textSizePx * 1.2F;
  const int measureMaxWidthPx = static_cast<int>(baseGeo.MaxTitleBarWidth() - baseGeo.barX0 - titlePadding * 2.F);

  const auto titleTex = measureMaxWidthPx > 0
    ? data.decoration->GetTitleTexture(window->m_title, textSizePx, borderAlpha, fontFamily, measureMaxWidthPx, isActive)
    : nullptr;
  const float texW = (titleTex && titleTex->ok()) ? static_cast<float>(titleTex->m_size.x) : 0.F;

  // Plateau grows to fit the measured text + padding, floored at 20% of the
  // total width regardless of how short (or absent) the title is.
  const float desiredTitleBarWidthPx = baseGeo.barX0 + texW + titlePadding * 2.F;
  const auto geo = baseGeo.WithTitleBarWidth(desiredTitleBarWidthPx);

  // In fullSpan mode the outer path's shape is fixed regardless of text
  // width (see GetBorderTexture), so pass a value that doesn't fluctuate
  // with title length - otherwise every title change would needlessly
  // regenerate an identical border texture.
  const float borderTitleBarWidthPx = geo.fullSpan ? geo.MaxTitleBarWidth() : geo.titleBarWidth;
  const float outlinePx = static_cast<float>(PluginState->config.outlineSize->value()) * monitor->m_scale;
  const CHyprColor outlineColor{static_cast<uint64_t>(PluginState->config.outlineColor->value())};

  const auto tex = data.decoration->GetBorderTexture({box.w, box.h}, extentPx, chamferPx, gradient, titleBarHeightPx, borderTitleBarWidthPx, glowPx, glowStrength, outlinePx, outlineColor);
  if (!tex || !tex->ok())
    return {};

  std::vector<UP<IPassElement>> children;

  // Emitted first so it lands under the frame - which matters, because the
  // shadow does run under the frame's own outline (only the window's interior
  // is cleared out of it), and the frame is what hides that cut.
  const float shadowSizePx = static_cast<float>(PluginState->config.shadowSize->value()) * monitor->m_scale;
  const auto configOffset = PluginState->config.shadowOffset->value();
  const Vector2D shadowOffsetPx = {configOffset.x * monitor->m_scale, configOffset.y * monitor->m_scale};
  const CHyprColor shadowColor{static_cast<uint64_t>(PluginState->config.shadowColor->value())};

  if (const auto shadowTex = data.decoration->GetShadowTexture({box.w, box.h}, extentPx, chamferPx, titleBarHeightPx, borderTitleBarWidthPx, shadowSizePx, shadowColor, shadowOffsetPx);
      shadowTex && shadowTex->ok()) {
    const float margin = ChromeDecoration::ShadowMarginPx(shadowSizePx, shadowOffsetPx);

    CTexPassElement::SRenderData shadowData;
    shadowData.tex = shadowTex;
    shadowData.box = CBox{
      box.x - margin + shadowOffsetPx.x, box.y - margin + shadowOffsetPx.y,
      box.w + 2.0 * margin, box.h + 2.0 * margin,
    };
    shadowData.a = data.alpha;
    children.emplace_back(makeUnique<CTexPassElement>(shadowData));
  }

  CTexPassElement::SRenderData texData;
  texData.tex = tex;
  texData.box = box;
  texData.a = data.alpha;

  children.emplace_back(makeUnique<CTexPassElement>(texData));

  if (titleTex && titleTex->ok() && titleTex->m_size.x > 0 && titleTex->m_size.y > 0) {
    const float texH = static_cast<float>(titleTex->m_size.y);
    const float localX = geo.barX0 + titlePadding;
    const float localY = (geo.barBottom - texH) / 2.F;

    CTexPassElement::SRenderData titleData;
    titleData.tex = titleTex;
    titleData.box = CBox{box.x + localX, box.y + localY, texW, texH};
    titleData.a = data.alpha;
    children.emplace_back(makeUnique<CTexPassElement>(titleData));
  }

  return children;
}

bool ChromePassElement::needsLiveBlur() { return false; }

bool ChromePassElement::needsPrecomputeBlur() { return false; }

std::optional<CBox> ChromePassElement::boundingBox() {
  const auto monitor = g_pHyprRenderer->m_renderData.pMonitor.lock();
  if (!monitor)
    return std::nullopt;

  return data.decoration->FullDecorationExtentGlobal()
    .translate(-monitor->m_position)
    .expand(4 + ChromeDecoration::ShadowMarginLogical());
}