Quite buggy text drawing via FreeType + SDL2

core/dub.sdl

@@ -1,4 +1,5 @@
 name "core"
 license "LGPL-3.0"
+dependency "bindbc-freetype" version="~>1.0.5"
 targetType "library"
 targetName "hibiscore"

core/source/core/engine.d

@@ -10,6 +10,9 @@ import std.datetime.stopwatch;
 import std.stdio;
 import std.format;
 
+import bindbc.freetype;
+import bindbc.freetype.bind;
+
 class Engine {
 	this(Renderer renderer, LoggerCallback logger) {
 		this.renderer = renderer;
@@ -18,10 +21,17 @@ class Engine {
 		previousPhysicsProcessTick = 0.00001f;
 
 		watch.start();
+
+		this.loggerCallback(LoggingSeverity.Information, "Loading FreeType...");
+
+		freetypeSupport = loadFreeType();
+		FT_Init_FreeType(&freetypeLib);
+
 		this.loggerCallback(LoggingSeverity.Information, "Started Hibis!");
 	}
 
 	~this() {
+		FT_Done_FreeType(freetypeLib);
 		watch.stop();
 	}
 
@@ -58,6 +68,9 @@ class Engine {
 		}
 	}
 
+	private FTSupport freetypeSupport;
+	public FT_Library freetypeLib;
+
 	private Renderer renderer;
 	private StopWatch watch;
 	private float previousProcessTick;

core/source/graphics/drawable.d

@@ -2,5 +2,5 @@ module hibis.graphics.drawable;
 import hibis.renderer.renderer;
 
 abstract class Drawable {
-	void draw(Renderer* renderer);
+	public void draw(Renderer* renderer);
 }

core/source/logging/types.d

@@ -1,6 +1,6 @@
 module hibis.logging.types;
 
-enum LoggingSeverity {
+enum LoggingSeverity : ubyte {
 	Message = 0,
 	Information,
 	Warning,

core/source/renderer/renderer.d

@@ -1,12 +1,15 @@
 module hibis.renderer.renderer;
 
 import hibis.math.types;
+import hibis.resources.font;
 
 abstract class Renderer {
 	// Draw
 	void clearScreen(Color col);
 	void renderCurrent();
 
+	void drawText(Font font, string text, int size, IntVec2 pos);
+
 	// Pre and Post draw
 	void preDraw();
 	void postDraw();

core/source/resources/font.d

@@ -0,0 +1,18 @@
+module hibis.resources.font;
+
+import hibis.resources.resource;
+import bindbc.freetype.bind;
+
+import std.string : toStringz;
+
+class Font : Resource {
+	this(FT_Library freetypeLibrary, string path) {
+		FT_New_Face(freetypeLibrary, cast(char*)toStringz(path), 0, &face);
+	}
+
+	~this() {
+	    FT_Done_Face(face);
+	}
+
+	public FT_Face face;
+}

renderer/rsdl/dub.sdl

@@ -1,6 +1,7 @@
 name "rsdl"
 dependency "hibis:core" version=">=0.0.0"
 dependency "bindbc-sdl" version="~>1.3.5"
+dependency "bindbc-freetype" version="~>1.0.5"
 targetType "library"
 targetName "hibis_rsdl"
 # Source paths so this can compile properly

renderer/rsdl/source/hibis_rsdl.d

@@ -1,12 +1,17 @@
 module hibis_rsdl;
 
 import bindbc.sdl;
+import bindbc.freetype.bind;
+import bindbc.freetype.bind.ftbitmap;
 import hibis.renderer.renderer;
+import hibis.resources.font;
 import hibis.math.types;
 import std.exception;
 import std.format;
 
+import std.stdio;
 import std.string : toStringz;
+import core.stdcpp.vector;
 
 /** \class RSDL
 * Renderer implementation using SDL2 Renderer for the Hibis game engine
@@ -49,9 +54,28 @@ class RSDL : Renderer {
 	}
 
 	override void renderCurrent() {
+		SDL_UpdateWindowSurface(window);
 		SDL_RenderPresent(renderer);
 	}
 
+	override void drawText(Font font, string text, int size, IntVec2 pos) {
+		IntVec2 dupPos = { x: pos.x, y: pos.y };
+		dupPos.y += size-4;
+		FT_Set_Pixel_Sizes(font.face, size, size);
+		for (int character = 0; character < text.length; character++) {
+			if (text[character] == '\n') {
+				dupPos.x = pos.x;
+				dupPos.y += size;
+			} else {
+				FT_Load_Char(font.face, text[character], FT_LOAD_RENDER);
+
+				drawBitmap(font.face.glyph.bitmap, size, dupPos.x + font.face.glyph.bitmap_left, dupPos.y - font.face.glyph.bitmap_top);
+
+				dupPos.x += size;
+			}
+		}
+	}
+
 	override void preDraw() {}
 	override void postDraw() {}
 
@@ -65,6 +89,25 @@ class RSDL : Renderer {
 
 	override void setWindowTitle(string title) {}
 
+	private void drawBitmap(FT_Bitmap bitmap, int size, int x, int y) {
+		SDL_Surface* glyph = SDL_CreateRGBSurfaceFrom(bitmap.buffer, bitmap.width, bitmap.rows, 8, bitmap.pitch, 0, 0, 0, 0xFF);
+
+		SDL_SetSurfaceBlendMode(glyph, 0);
+
+		SDL_Color[256] colors;
+		for (int i = 0; i < 256; i++) {
+			ubyte newC = cast(ubyte)i;
+			colors[i].r = colors[i].g = colors[i].b = newC;
+		}
+		SDL_SetPaletteColors(glyph.format.palette, cast(const(SDL_Color)*)colors, 0, 256);
+
+		SDL_Rect dest = { x, y, size, size};
+		SDL_Texture* texture = SDL_CreateTextureFromSurface(renderer, glyph);
+		SDL_RenderCopy(renderer, texture, null, &dest);
+		SDL_DestroyTexture(texture);
+		SDL_FreeSurface(glyph);
+	}
+
 	private SDL_Window* window;
 	private SDL_Renderer* renderer;
 }

test/source/app.d

@@ -5,6 +5,7 @@ import std.conv;
 import hibis.core.engine;
 import hibis.math.types;
 import hibis.renderer.renderer;
+import hibis.resources.font;
 import hibis.logging.types;
 import hibis.callback;
 import hibis_rsdl;
@@ -18,7 +19,11 @@ void logger(LoggingSeverity severity, string message) {
 void main() {
 	Renderer renderer = new RSDL("test", IntVec2(800, 600));
 	Engine engine = new Engine(renderer, &logger);
-
+	version(windows) {
+		Font font = new Font(engine.freetypeLib, "C:\\Windows\\Fonts\\Arial.ttf");
+	} else {
+		Font font = new Font(engine.freetypeLib, "/usr/share/fonts/noto/NotoSans-Light.ttf");
+	}
 	ubyte red = 0;
 	bool increase = true;
 
@@ -35,10 +40,12 @@ void main() {
 
 		// Clear screen then sleep for ~16ms
 		renderer.clearScreen(Color(red, 0, 0, 255));
+		renderer.drawText(font, "TEST", 16, IntVec2(0, 0));
 
 		engine.drawNodes();
 		renderer.renderCurrent();
 		renderer.update();
 		Thread.sleep(16.msecs);
 	}
+	destroy(font);
 }