From 7850628ff1029a4a6eeb0b4f1db3eb15e4e26f97 Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Mon, 28 Mar 2022 13:40:48 +0200
Subject: [PATCH] LibGfx: Add Painter::draw_text_run(), a simplified text
 painting API

This API does:
    - Take a Utf8View
    - Take the starting point on the baseline as its input coordinate

This API does not:
    - Align the text
    - Wrap the text
    - Elide too-long text into "..."
---
 Userland/Libraries/LibGfx/Painter.cpp | 19 +++++++++++++++++++
 Userland/Libraries/LibGfx/Painter.h   |  3 +++
 2 files changed, 22 insertions(+)

diff --git a/Userland/Libraries/LibGfx/Painter.cpp b/Userland/Libraries/LibGfx/Painter.cpp
index 8b68f22741..05603ab0f3 100644
--- a/Userland/Libraries/LibGfx/Painter.cpp
+++ b/Userland/Libraries/LibGfx/Painter.cpp
@@ -2314,4 +2314,23 @@ void Gfx::Painter::draw_ui_text(Gfx::IntRect const& rect, StringView text, Gfx::
         }
     }
 }
+
+void Painter::draw_text_run(FloatPoint const& baseline_start, Utf8View const& string, Font const& font, Color color)
+{
+    auto pixel_metrics = font.pixel_metrics();
+    float x = baseline_start.x();
+    int y = baseline_start.y() - pixel_metrics.ascent;
+    float space_width = font.glyph_or_emoji_width(' ');
+
+    for (auto code_point : string) {
+        if (code_point == ' ') {
+            x += space_width;
+            continue;
+        }
+        float advance = font.glyph_or_emoji_width(code_point) + font.glyph_spacing();
+        draw_glyph_or_emoji({ (int)roundf(x), y }, code_point, font, color);
+        x += advance;
+    }
+}
+
 }
diff --git a/Userland/Libraries/LibGfx/Painter.h b/Userland/Libraries/LibGfx/Painter.h
index fedb6433ca..744702745c 100644
--- a/Userland/Libraries/LibGfx/Painter.h
+++ b/Userland/Libraries/LibGfx/Painter.h
@@ -87,6 +87,9 @@ public:
     void draw_glyph_or_emoji(IntPoint const&, Utf8CodePointIterator&, Font const&, Color);
     void draw_circle_arc_intersecting(IntRect const&, IntPoint const&, int radius, Color, int thickness);
 
+    // Streamlined text drawing routine that does no wrapping/elision/alignment.
+    void draw_text_run(FloatPoint const& baseline_start, Utf8View const&, Font const&, Color);
+
     enum class CornerOrientation {
         TopLeft,
         TopRight,