add ttf font

scripts/nvboard.mk

@@ -26,7 +26,7 @@ $(NVBOARD_ARCHIVE): $(NVBOARD_OBJS)
 -include $(NVBOARD_OBJS:.o=.d)
 
 # Link flags for examples
-LDFLAGS += $(shell sdl2-config --libs) -lSDL2_image
+LDFLAGS += $(shell sdl2-config --libs) -lSDL2_image -lSDL2_ttf
 
 .PHONY: nvboard-archive nvboard-clean
 

src/font.cpp

@@ -0,0 +1,28 @@
+#include <nvboard.h>
+#include <SDL_ttf.h>
+
+static TTF_Font *font = NULL;
+
+void init_font() {
+  int ret = TTF_Init();
+  assert(ret != -1);
+  std::string nvboard_home = getenv("NVBOARD_HOME");
+  font = TTF_OpenFont((nvboard_home + "/resources/font/" + "FreeMono.ttf").c_str(), 28);
+  assert(font != NULL);
+}
+
+void test_font(SDL_Renderer *renderer) {
+  SDL_Color c = {.r = 0xff, .g = 0xff, .b = 0xff };
+  SDL_Surface *s = TTF_RenderText_Solid_Wrapped(font, "abc", c, 0);
+  SDL_Texture *t = SDL_CreateTextureFromSurface(renderer, s);
+  SDL_Rect r = { 0, 0, s->w, s->h };
+  SDL_RenderCopy(renderer, t, NULL, &r);
+  SDL_FreeSurface(s);
+  SDL_DestroyTexture(t);
+}
+
+void close_font() {
+  TTF_CloseFont(font);
+  font = NULL;
+  TTF_Quit();
+}

src/nvboard.cpp

@@ -82,6 +82,11 @@ void nvboard_init(int vga_clk_cycle) {
     init_components(main_renderer);
     init_gui(main_renderer);
 
+    void init_font();
+    void test_font(SDL_Renderer *renderer);
+    init_font();
+    test_font(main_renderer);
+
     for (int i = 0; i < NR_PINS; i ++) {
       if (pin_array[i].ptr == NULL) pin_array[i].ptr = &pin_array[i].data;
     }