font/sdl_ttf_compat: Implement draw_text() substitute

This doesn't support GUI1 markup, intentionally.

src/font/sdl_ttf_compat.cpp

@@ -15,7 +15,10 @@
 #include "font/sdl_ttf_compat.hpp"
 
 #include "log.hpp"
+#include "sdl/utils.hpp"
 #include "serialization/unicode.hpp"
+#include "tooltips.hpp"
+#include "video.hpp"
 
 static lg::log_domain log_font("font");
 #define DBG_FT LOG_STREAM(debug, log_font)
@@ -130,4 +133,47 @@ std::string pango_word_wrap(const std::string& unwrapped_text, int font_size, in
 	return res;
 }
 
+SDL_Rect pango_draw_text(CVideo* gui, const SDL_Rect& area, int size, const color_t& color, const std::string& text, int x, int y, bool use_tooltips, pango_text::FONT_STYLE style)
+{
+	static surface null_surf{};
+
+	return pango_draw_text(gui != nullptr ? gui->getSurface() : null_surf, area, size, color, text, x, y, use_tooltips, style);
+}
+
+SDL_Rect pango_draw_text(surface& dst, const SDL_Rect& area, int size, const color_t& color, const std::string& text, int x, int y, bool use_tooltips, pango_text::FONT_STYLE style)
+{
+	auto& ptext = private_renderer();
+
+	ptext.set_text(text, false);
+	ptext.set_font_size(size)
+		 .set_font_style(style)
+		 .set_maximum_width(-1)
+		 .set_maximum_height(area.h, true)
+		 .set_foreground_color(color)
+		 .set_ellipse_mode(PANGO_ELLIPSIZE_END);
+
+	auto s = ptext.render();
+
+	bool ellipsized = false;
+
+	if(s->w > area.w) {
+		ptext.set_maximum_width(area.w);
+		s = ptext.render();
+		ellipsized = true;
+	}
+
+	SDL_Rect res = { x, y, s->w, s->h };
+
+	if(dst) {
+		SDL_Rect src = { 0, 0, s->w, s->h };
+		sdl_blit(s, &src, dst, &res);
+	}
+
+	if(ellipsized && use_tooltips) {
+		tooltips::add_tooltip(res, text);
+	}
+
+	return res;
+}
+
 } // end namespace font

src/font/sdl_ttf_compat.hpp

@@ -17,10 +17,19 @@
 /**
  * @file
  * Transitional API for porting SDL_ttf-based code to Pango. Do NOT use in new code!
+ *
+ * @note GUI1 markup is not supported by this transitional API for cost-benefit reasons.
+ * Not only does implementing it require a lot more work to go over text line by line,
+ * it also had major design flaws -- namely, only applying to whole lines with variable
+ * spans that would be decided by the layout algorithm depending on available space,
+ * rather than on a physical line basis (markup start till EOL) or fixed span basis (e.g.
+ * the special markup used by the Help browser, or Pango markup).
  */
 
 #include "font/text.hpp"
 
+class CVideo;
+
 namespace font {
 
 /**
@@ -51,4 +60,26 @@ std::string pango_line_ellipsize(const std::string& text, int font_size, int max
  */
 std::string pango_word_wrap(const std::string& unwrapped_text, int font_size, int max_width, int max_height = -1, int max_lines = -1, bool partial_line = false);
 
+/**
+ * Draws text on a surface.
+ *
+ * The text will be clipped to area.  If the text runs outside of area
+ * horizontally, an ellipsis will be displayed at the end of it.
+ *
+ * If use_tooltips is true, then text with an ellipsis will have a tooltip
+ * set for it equivalent to the entire contents of the text.
+ *
+ * A bounding rectangle of the text is returned. If dst is nullptr, then the
+ * text will not be drawn, and a bounding rectangle only will be returned.
+ */
+SDL_Rect pango_draw_text(surface& dst, const SDL_Rect& area, int size, const color_t& color, const std::string& text, int x, int y, bool use_tooltips = false, pango_text::FONT_STYLE style = pango_text::STYLE_NORMAL);
+
+/**
+ * Draws text on the screen.
+ *
+ * gui can be nullptr, in which case the bounding rectangle will still be
+ * returned.
+ */
+SDL_Rect pango_draw_text(CVideo* gui, const SDL_Rect& area, int size, const color_t& color, const std::string& text, int x, int y, bool use_tooltips = false, pango_text::FONT_STYLE style = pango_text::STYLE_NORMAL);
+
 } // end namespace font