add text out capabilities using FreeType and the Inconsolata font

scripts/tmp_main.py

@@ -19,3 +19,4 @@ upiwin_tmp.filled_rectangle(110, 60, 150, 100, FBPRIMCLR_YELLOW, False)
 upiwin_tmp.rectangle(10, 110, 150, 150, FBPRIMCLR_WHITE, False)
 upiwin_tmp.line(10, 110, 150, 150, FBPRIMCLR_WHITE, False)
 upiwin_tmp.line(10, 150, 150, 110, FBPRIMCLR_WHITE, False)
+upiwin_tmp.textout(10, 180, 'Amy was here!!!')

src/Makefile

@@ -1,7 +1,8 @@
-OBJS=main.o sysinput.o ep_init.o ep_upiwin.o ep_backlight.o ep_upiwin_tmp.o ep_util.o fbinit.o fbprimitive.o \
+OBJS=main.o sysinput.o ep_init.o ep_upiwin.o ep_backlight.o ep_upiwin_tmp.o ep_util.o fbinit.o fontengine.o 6fbprimitive.o \
      log.o gpio.o msg_queue.o time_func.o config.o splash.o
-LIBS=-lpython3.7m -lcrypt -lbcm2835 -lpthread -ldl -lutil -lm
-CFLAGS=-I/usr/include/python3.7m -Wall -fstack-protector -fwrapv -fno-PIE -g -O3 -DDEBUG_ASSERT
+LIBS=-lpython3.7m -lcrypt -lfreetype -lbcm2835 -lpthread -ldl -lutil -lm
+CFLAGS=-I/usr/include/python3.7m -I/usr/include/freetype2 -I/usr/include/libpng16 \
+       -Wall -fstack-protector -fwrapv -fno-PIE -g -O3 -DDEBUG_ASSERT
 LDFLAGS=-L/usr/lib/python3.7/config-3.7m-arm-linux-gnueabihf -Xlinker -export-dynamic -Wl,-O1 \
         -Wl,-Bsymbolic-functions
 

src/ep_upiwin_tmp.c

@@ -52,11 +52,23 @@ static PyObject *do_filled_rectangle(PyObject *self, PyObject *args)
   Py_RETURN_NONE;
 }
 
+static PyObject *do_textout(PyObject *self, PyObject *args)
+{
+  INT32 x, y;
+  PSTR text;
+
+  if (!PyArg_ParseTuple(args, "iis", &x, &y, &text))
+    return NULL;
+  Fb_textout(x, y, text);
+  Py_RETURN_NONE;
+}
+
 static PyMethodDef UPIWIN_tmpMethods[] = {
   {"setpixel", do_setpixel, METH_VARARGS, "Set a single pixel on the display."},
   {"line", do_line, METH_VARARGS, "Draw a line on the display."},
   {"rectangle", do_rectangle, METH_VARARGS, "Draw a rectangle on the display."},
   {"filled_rectangle", do_filled_rectangle, METH_VARARGS, "Draw a filled rectangle on the display."},
+  {"textout", do_textout, METH_VARARGS, "Draw text on the display."},
   {NULL, NULL, 0, NULL}
 };
 

src/fbprimitive.c

@@ -1,3 +1,4 @@
+#include <alloca.h>
 #include "wintype.h"
 #include "fbinit.h"
 
@@ -112,3 +113,33 @@ void Fb_filled_rectangle(INT32 x1, INT32 y1, INT32 x2, INT32 y2, UINT16 color, B
     ps += Fb_Info->width;
   }
 }
+
+static void internal_textout(INT32 x, INT32 y, INT32 width, INT32 height, PBYTE gsbits)
+{
+  INT32 i, j;
+  BYTE b;
+  PUINT16 dptr, lbuf;
+  
+  if (((x + width) >= Fb_Info->width) || ((y + height) >= Fb_Info->height))
+    return;
+  dptr = loc_from_coords(x, y);
+  lbuf = (PUINT16)alloca(width * sizeof(UINT16));
+  for (i=0; i<height; i++)
+  {
+    for (j=0; j<width; j++)
+    {
+      b = *gsbits++;
+      lbuf[i] = ((UINT16)(b >> 3) & 0x1F) << 11;
+      lbuf[i] |= ((UINT16)(b >> 2) & 0x3F) << 5;
+      lbuf[i] |= ((UINT16)(b >> 3) & 0x1F);
+    }
+
+    memcpy(dptr, lbuf, width * sizeof(UINT16));
+    dptr += Fb_Info->width;
+  }
+}
+
+void Fb_textout(INT32 x, INT32 y, PCSTR pstr)
+{
+  FontEng_do_text_out(x, y, pstr, internal_textout);
+}

src/fbprimitive.h

@@ -17,5 +17,6 @@ extern UINT16 Fb_setpixel(INT32 x, INT32 y, UINT16 color, BOOL xor);
 extern void Fb_line(INT32 x1, INT32 y1, INT32 x2, INT32 y2, UINT16 color, BOOL xor);
 extern void Fb_rectangle(INT32 x1, INT32 y1, INT32 x2, INT32 y2, UINT16 color, BOOL xor);
 extern void Fb_filled_rectangle(INT32 x1, INT32 y1, INT32 x2, INT32 y2, UINT16 color, BOOL xor);
+extern void Fb_textout(INT32 x, INT32 y, PCSTR pstr);
 
 #endif /* __FBPRIMITIVE_H_INCLUDED */

src/fontengine.c

@@ -0,0 +1,84 @@
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include "scode.h"
+#include "config.h"
+#include "log.h"
+#include "fontengine.h"
+
+static FT_LIbrary library;
+static FT_Face stdfont;
+
+static void fonteng_cleanup(void)
+{
+  FT_Done_Face(stdfont);
+  FT_Done_FreeType(library);
+}
+
+HRESULT FontEng_setup(void)
+{
+  HRESULT hr = S_OK;
+  FT_Error err;
+  
+  err = FT_Init_FreeType(&library);
+  if (err != 0)
+  {
+    Log(LFATAL, "Unable to initialize Freetype (%d)", err);
+    return E_FAIL;
+  }
+
+  err = FT_New_Face(library, "/usr/local/share/fonts/opentype/Inconsolata.otf", 0, &stdfont);
+  if (err != 0)
+  {
+    Log(LFATAL, "Unable to load font (%d)", err);
+    hr = E_FAIL;
+    goto error_0;
+  }
+
+  err = FT_Set_Pixel_Sizes(stdfont, 0, 16);
+  if (err != 0)
+  {
+    Log(LFATAL, "Unable to set font size (%d)", err);
+    hr = E_FAIL;
+    goto error_1;
+  }
+
+  hr = Config_exitfunc(fonteng_cleanup);
+  if (FAILED(hr))
+    fonteng_cleanup();
+  return hr;
+
+error_1:
+  FT_Done_Face(stdfont);
+error_0:
+  FT_Done_FreeType(library);
+  return hr;
+}
+
+HRESULT FontEng_do_text_out(INT32 x, INT32 y, PCSTR pstr, TEXTOUTFUNC renderfunc)
+{
+  HRESULT hr = S_OK;
+  FT_GlyphSlot slot = stdfont->glyph;
+  FT_UInt glyph_index;
+  FT_Error err;
+
+  while (*pstr)
+  {
+    glyph_index = FT_Get_Char_Index(stdfont, *pstr++);
+    err = FT_Load_Glyph(stdfont, glyph_index, FT_LOAD_DEFAULT);
+    if (err != 0)
+    {
+      hr = E_FAIL;
+      break;
+    }
+    err = FT_Render_Glyph(stdfont->glyph, FT_RENDER_MODE_NORMAL);
+    if (err != 0)
+    {
+      hr = E_FAIL;
+      break;
+    }
+    (*renderfunc)(x, y, slot->bitmap.width, slot->bitmap.rows, slot->bitmap.buffer);
+    x += slot->advance.x >> 6;
+    y += slot->advance.y >> 6;
+  }
+  return hr;
+}

src/fontengine.h

@@ -0,0 +1,11 @@
+#ifndef __FONTENGINE_H_INCLUDED
+#define __FONTENGINE_H_INCLUDED
+
+#include "wintype.h"
+
+typedef void (*TEXTOUTFUNC)(INT32 x, INT32 y, INT32 width, INT32 height, PBYTE gsbits);
+
+extern HRESULT FontEng_setup(void);
+extern HRESULT FontEng_do_text_out(INT32 x, INT32 y, PCSTR pstr, TEXTOUTFUNC renderfunc);
+
+#endif /* __FONTENGINE_H_INCLUDED */

src/main.c

@@ -31,6 +31,8 @@ int main(int argc, char *argv[])
     return EXIT_SUCCESS;
   if (FAILED(Fb_setup()))
     return EXIT_FAILURE;
+  if (FAILED(FontEng_setup()))
+    return EXIT_FAILURE;
   if (FAILED(Gpio_setup()))
     return EXIT_FAILURE;
   if (FAILED(Epython_setup()))