glfont.cpp

#include "glfont.h"

#define STB_TRUETYPE_IMPLEMENTATION // force following include to generate
                                    // implementation
#include "stb_truetype.h"

#include "filesys.h"
#include "glprog.h"

extern ProgramData g_progBasicTex;
extern GLuint g_testVertexArrays;

glFont::glFont() : bakedFont("Baked Font") {
  pixelHeight = 32.0f;
  codePointStart = 32;
  codePointEnd = 96;
  cdata = nullptr;
}

glFont::~glFont() {
  if (cdata != nullptr)
    delete[] cdata;
}

void glFont::Init(const char *filename) {
  cdata = nullptr;

  // Setup Image for Baking
  bakedFont.height = 512;
  bakedFont.width = 512;
  bakedFont.imgType = GL_ALPHA;
  bakedFont.imgData = new u8[bakedFont.height * bakedFont.width];

  // Read File into Buffer
  auto ttf_buffer = ReadFileToBuffer(filename);

  // Bake Font to Image
  cdata = new stbtt_bakedchar[codePointEnd - codePointStart];
  stbtt_BakeFontBitmap(&ttf_buffer[0], 0, pixelHeight, bakedFont.imgData,
                       bakedFont.width, bakedFont.height, codePointStart,
                       codePointEnd,
                       (stbtt_bakedchar *)cdata); // no guarantee this fits!
  ttf_buffer.clear();

  // Copy to GPU
  bakedFont.CopyToGPU();
  bakedFont.FreeImage();
}

GLuint glFont::GenBindVertList(float x, float y,
                               const std::vector<char> &text) {
  stbtt_bakedchar *cdata_typed = (stbtt_bakedchar *)cdata;

  std::vector<stbtt_aligned_quad> charQuads;
  for (const char &c : text) {
    if ((c < codePointStart) || (c >= codePointEnd)) {
      x += pixelHeight * 0.5f;
      continue;
    }

    stbtt_aligned_quad q;
    stbtt_GetBakedQuad(cdata_typed, bakedFont.width, bakedFont.height, c, &x,
                       &y, &q,
                       1); // 1=opengl

    charQuads.push_back(q);
  }

  int i = 0;
  GLuint numFloats = (GLuint)(charQuads.size() * 8);
  GLfloat *vData = new GLfloat[numFloats];

  for (const stbtt_aligned_quad &q : charQuads) {
    vData[i++] = q.s0;
    vData[i++] = q.t1;
    vData[i++] = q.x0;
    vData[i++] = q.y0;

    vData[i++] = q.s1;
    vData[i++] = q.t1;
    vData[i++] = q.x1;
    vData[i++] = q.y0;

    vData[i++] = q.s1;
    vData[i++] = q.t0;
    vData[i++] = q.x1;
    vData[i++] = q.y1;

    vData[i++] = q.s0;
    vData[i++] = q.t0;
    vData[i++] = q.x0;
    vData[i++] = q.y1;
  }

  GLuint newVertArray;

  glGenVertexArrays(1, &newVertArray);
  glBindVertexArray(newVertArray);

  ProgramData *prog = ProgramData::GetProg(PD_BASIC_TEX);
  genBasicFloatNBuffer(0, prog->attribList[0], vData, numFloats, 4);

  return 0; // Can't recall what I was doing here blame the meds
}