add newline feature to the text node, add about window with credits, add about menu with submenus

src/font.cpp

@@ -19,6 +19,7 @@ bool Font::load(const char* ttf, int font_size)
         stbtt_BakeFontBitmap(file.m_data, 0, (float)font_size*2, bitmap.get(), w, h, start_char, num_chars, chars.data());
         font_tex.create(w, h, GL_R8, GL_RED, bitmap.get());
         file.close();
+        size = font_size;
         return true;
     }
     return false;
@@ -71,6 +72,12 @@ void TextMesh::update(kFont id, const char* text)
         glm::vec2 bbmax(-FLT_MAX);
         for (int i = 0; i < len; i++)
         {
+            if (text[i] == '\n')
+            {
+                x = 0;
+                y += f.size *2;
+                continue;
+            }
             int c = text[i] - f.start_char;
             stbtt_aligned_quad q;
             stbtt_GetBakedQuad((stbtt_bakedchar*)f.chars.data(), f.w, f.h, c, &x, &y, &q, true);
@@ -88,10 +95,8 @@ void TextMesh::update(kFont id, const char* text)
             bbmin = glm::min(bbmin, { q.x0/2.f, q.y0/2.f });
             bbmax = glm::max(bbmax, { q.x1/2.f, q.y1/2.f });
         }
-        for (int i = 0; i < len*4; i++)
-        {
-            v[i] -= glm::vec4(bbmin, 0, 0);
-        }
+        for (auto& vi : v)
+            vi -= glm::vec4(bbmin, 0, 0);
         bb = bbmax - bbmin;
         font_array_count = (int)idx.size();
         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, font_buffers[1]);