From 5e6b1cfdfc4189c9cc07647d277d5076c4089999 Mon Sep 17 00:00:00 2001
From: bmcorser <bmcorser@gmail.com>
Date: Wed, 14 Mar 2018 10:50:54 +0000
Subject: [PATCH] Simple demo

---
 demo-simple/build-run.sh   |  11 ++++
 demo-simple/demo-simple.cc | 115 +++++++++++++++++++++++++++++++++++++
 2 files changed, 126 insertions(+)
 create mode 100755 demo-simple/build-run.sh
 create mode 100644 demo-simple/demo-simple.cc

diff --git a/demo-simple/build-run.sh b/demo-simple/build-run.sh
new file mode 100755
index 00000000..0aefd6eb
--- /dev/null
+++ b/demo-simple/build-run.sh
@@ -0,0 +1,11 @@
+#!/bin/bash
+g++ demo-simple.cc \
+    -I../src \
+    -I/usr/include/freetype2 \
+    -I../demo \
+    -L../src/.libs \
+    -lglyphy \
+    -lfreetype \
+    -o demo-simple
+
+LD_LIBRARY_PATH=../src/.libs ./demo-simple
diff --git a/demo-simple/demo-simple.cc b/demo-simple/demo-simple.cc
new file mode 100644
index 00000000..dee96119
--- /dev/null
+++ b/demo-simple/demo-simple.cc
@@ -0,0 +1,115 @@
+#include <stdio.h>
+#include <vector>
+#include <iostream>
+
+#include "ft2build.h"
+
+#include <glyphy-freetype.h>
+
+#include "default-font.h"
+
+static FT_Int32 GLYPH_LOAD_FLAGS = \
+  FT_LOAD_NO_BITMAP |
+  FT_LOAD_NO_HINTING |
+  FT_LOAD_NO_AUTOHINT |
+  FT_LOAD_NO_SCALE |
+  FT_LOAD_LINEAR_DESIGN |
+  FT_LOAD_IGNORE_TRANSFORM;
+
+static glyphy_bool_t
+accumulate_endpoint (glyphy_arc_endpoint_t *endpoint,
+                     std::vector<glyphy_arc_endpoint_t> *endpoints)
+{
+  endpoints->push_back (*endpoint);
+  return true;
+}
+
+
+int main() {
+  FT_Library ft_library;
+  FT_Init_FreeType (&ft_library);
+  FT_Face ft_face = NULL;
+  FT_New_Face (ft_library, ".", 0, &ft_face);
+  FT_New_Memory_Face (ft_library,
+                      (const FT_Byte *) default_font,
+                      sizeof (default_font),
+                      0,
+                      &ft_face);
+  if (!ft_face) {
+    printf("FT_New_Memory_Face failed\n");
+  }
+  FT_ULong latin_capital_G = 0x47;
+  unsigned int glyph_index = FT_Get_Char_Index (ft_face, latin_capital_G);
+  if (FT_Err_Ok != FT_Load_Glyph (ft_face, glyph_index, GLYPH_LOAD_FLAGS)) {
+    printf("FT_Load_Glyph failed\n");
+  }
+  double default_tolerance = (1.0 / 2048);
+  FT_UShort upem = ft_face->units_per_EM;
+  double tolerance = default_tolerance * upem;
+  std::vector<glyphy_arc_endpoint_t> endpoints;
+
+  glyphy_arc_accumulator_t* acc = glyphy_arc_accumulator_create();
+  glyphy_arc_accumulator_reset (acc);
+  glyphy_arc_accumulator_set_tolerance (acc, tolerance);
+  glyphy_arc_accumulator_set_callback (
+    acc,
+    (glyphy_arc_endpoint_accumulator_callback_t) accumulate_endpoint,
+    &endpoints
+  );
+
+  FT_Error decomposition_result = glyphy_freetype(outline_decompose) (&ft_face->glyph->outline, acc);
+
+  if (FT_Err_Ok != decomposition_result)
+    printf("FT_Outline_Decompose failed\n");
+
+  glyphy_outline_winding_from_even_odd (&endpoints[0], endpoints.size (), false);
+
+  glyphy_rgba_t buffer[4096 * 16];
+  signed int buffer_len = sizeof (buffer) / sizeof (buffer[0]);
+  #define SCALE  (1. * (1 << 0))
+  #define MIN_FONT_SIZE 10
+  #define M_SQRT2 1.4142135623730951
+  double faraway = upem / (MIN_FONT_SIZE * M_SQRT2);
+  double avg_fetch_achieved;
+	unsigned int output_len;
+	unsigned int nominal_width;
+	unsigned int nominal_height;
+	glyphy_extents_t extents;
+
+  if (!glyphy_arc_list_encode_blob (
+    endpoints.size () ? &endpoints[0] : NULL, endpoints.size (),
+    buffer,
+    buffer_len,
+    faraway / SCALE,
+    4, // UNUSED
+    &avg_fetch_achieved,
+    &output_len,
+    &nominal_width,
+    &nominal_height,
+    &extents))
+    printf("glyphy_arc_list_encode_blob failed\n");
+
+  glyphy_extents_scale (&extents, 1. / upem, 1. / upem);
+  glyphy_extents_scale (&extents, SCALE, SCALE);
+
+  // TODO:
+  // create GL program, attach simple pass-through vertex shader and glyphy sdf
+  // shader programs, bind buffer send glyphy data to buffer
+
+  /* from demo-buffer.cc+166
+  GLint program;
+  glGetIntegerv (GL_CURRENT_PROGRAM, &program);
+  GLuint a_glyph_vertex_loc = glGetAttribLocation (program, "a_glyph_vertex");
+  glBindBuffer (GL_ARRAY_BUFFER, buffer->buf_name);
+  if (buffer->dirty) {
+    glBufferData (GL_ARRAY_BUFFER,  sizeof (glyph_vertex_t) * buffer->vertices->size (), (const char *) &(*buffer->vertices)[0], GL_STATIC_DRAW);
+    buffer->dirty = false;
+  }
+  glEnableVertexAttribArray (a_glyph_vertex_loc);
+  glVertexAttribPointer (a_glyph_vertex_loc, 4, GL_FLOAT, GL_FALSE, sizeof (glyph_vertex_t), 0);
+  glDrawArrays (GL_TRIANGLES, 0, buffer->vertices->size ());
+  glDisableVertexAttribArray (a_glyph_vertex_loc);
+  */
+
+  return 0;
+}