From 155e76df5f4b8c2e68a47209f73dd1241b4acc78 Mon Sep 17 00:00:00 2001
From: Francesco Abbate <francesco.bbt@gmail.com>
Date: Sat, 30 May 2020 15:19:12 +0200
Subject: [PATCH] Add font vmetrics in AGG font renderer test

---
 src/font_render_lcd.h          | 13 +++++++++++++
 tests/agg_font_render_test.cpp |  4 ++++
 2 files changed, 17 insertions(+)

diff --git a/src/font_render_lcd.h b/src/font_render_lcd.h
index d24aebf2..d8ab9df2 100644
--- a/src/font_render_lcd.h
+++ b/src/font_render_lcd.h
@@ -55,6 +55,19 @@ public:
         m_gamma_lut.gamma(m_gamma);
     }
 
+    bool get_font_vmetrics(int& ascender, int& descender) {
+        int face_height = m_feng.face_height();
+        if (face_height > 0) {
+            double current_height = m_feng.height();
+            m_feng.height(1.0);
+            ascender  = m_feng.ascender()  * face_height;
+            descender = m_feng.descender() * face_height;
+            m_feng.height(current_height);
+            return true;
+        }
+        return false;
+    }
+
     bool load_font(const char *font_filename) {
         if(m_feng.load_font(font_filename, 0, agg::glyph_ren_outline)) {
             m_font_loaded = true;
diff --git a/tests/agg_font_render_test.cpp b/tests/agg_font_render_test.cpp
index ea0b2666..4dd1cba0 100644
--- a/tests/agg_font_render_test.cpp
+++ b/tests/agg_font_render_test.cpp
@@ -62,6 +62,10 @@ RenFontA* ren_load_font_agg(const char *filename, float size) {
   font->renderer = new font_renderer_lcd(true, false, false, 1.8);
   font->renderer->load_font(filename);
 
+  int ascender, descender;
+  font->renderer->get_font_vmetrics(ascender, descender);
+  fprintf(stderr, "Font metrics ascender: %d descender: %d\n", ascender, descender);
+
   // FIXME: figure out correct calculation for font->height with
   // ascent, descent and linegap.
   font->height = size;