refine dynamic font glyph placement

panda/src/text/dynamicTextFont.cxx

@@ -459,6 +459,9 @@ make_glyph(int glyph_index) {
   } else {
     DynamicTextGlyph *glyph;
 
+    float tex_x_size = bitmap.width;
+    float tex_y_size = bitmap.rows;
+
     if (_tex_pixels_per_unit == _font_pixels_per_unit) {
       // If the bitmap produced from the font doesn't require scaling
       // before it goes to the texture, we can just copy it directly
@@ -469,21 +472,27 @@ make_glyph(int glyph_index) {
     } else {
       // Otherwise, we need to copy to a PNMImage first, so we can
       // scale it; and then copy it to the texture from there.
-      int tex_x_size = (int)(bitmap.width / _scale_factor + 0.5f);
-      int tex_y_size = (int)(bitmap.rows / _scale_factor + 0.5f);
-      glyph = slot_glyph(tex_x_size, tex_y_size);
-
-      PNMImage image(bitmap.width, bitmap.rows, PNMImage::CT_grayscale);
+      tex_x_size /= _scale_factor;
+      tex_y_size /= _scale_factor;
+      int int_x_size = (int)ceil(tex_x_size);
+      int int_y_size = (int)ceil(tex_y_size);
+      int bmp_x_size = (int)(int_x_size * _scale_factor + 0.5f);
+      int bmp_y_size = (int)(int_y_size * _scale_factor + 0.5f);
+      glyph = slot_glyph(int_x_size, int_y_size);
+      
+      PNMImage image(bmp_x_size, bmp_y_size, PNMImage::CT_grayscale);
       copy_bitmap_to_pnmimage(bitmap, image);
 
-      PNMImage reduced(tex_x_size, tex_y_size, PNMImage::CT_grayscale);
+      PNMImage reduced(int_x_size, int_y_size, PNMImage::CT_grayscale);
       reduced.quick_filter_from(image);
       copy_pnmimage_to_texture(reduced, glyph);
     }
       
     glyph->_page->mark_dirty(Texture::DF_image);
     
-    glyph->make_geom(slot->bitmap_top, slot->bitmap_left, advance, _poly_margin,
+    glyph->make_geom(slot->bitmap_top, slot->bitmap_left,
+                     advance, _poly_margin,
+                     tex_x_size, tex_y_size,
                      _font_pixels_per_unit, _tex_pixels_per_unit);
     return glyph;
   }

panda/src/text/dynamicTextGlyph.cxx

@@ -109,26 +109,30 @@ erase() {
 ////////////////////////////////////////////////////////////////////
 void DynamicTextGlyph::
 make_geom(int bitmap_top, int bitmap_left, float advance, float poly_margin, 
+          float tex_x_size, float tex_y_size,
           float font_pixels_per_unit, float tex_pixels_per_unit) {
   nassertv(_page != (DynamicTextPage *)NULL);
 
   // This function should not be called twice.
   nassertv(_geom_count == 0);
 
+  tex_x_size += _margin * 2;
+  tex_y_size += _margin * 2;
+
   // Determine the corners of the rectangle in geometric units.
   float tex_poly_margin = poly_margin / tex_pixels_per_unit;
   float origin_y = bitmap_top / font_pixels_per_unit;
   float origin_x = bitmap_left / font_pixels_per_unit;
   float top = origin_y + tex_poly_margin;
   float left = origin_x - tex_poly_margin;
-  float bottom = origin_y - _y_size / tex_pixels_per_unit - tex_poly_margin;
-  float right = origin_x + _x_size / tex_pixels_per_unit + tex_poly_margin;
+  float bottom = origin_y - tex_y_size / tex_pixels_per_unit - tex_poly_margin;
+  float right = origin_x + tex_x_size / tex_pixels_per_unit + tex_poly_margin;
 
   // And the corresponding corners in UV units.
   float uv_top = 1.0f - (float)(_y - poly_margin) / _page->get_y_size();
   float uv_left = (float)(_x - poly_margin) / _page->get_x_size();
-  float uv_bottom = 1.0f - (float)(_y + _y_size + poly_margin) / _page->get_y_size();
-  float uv_right = (float)(_x + _x_size + poly_margin) / _page->get_x_size();
+  float uv_bottom = 1.0f - (float)(_y + poly_margin + tex_y_size) / _page->get_y_size();
+  float uv_right = (float)(_x + poly_margin + tex_x_size) / _page->get_x_size();
 
   // Create a corresponding tristrip.
   _geom = new GeomTextGlyph(this);

panda/src/text/dynamicTextGlyph.h

@@ -51,6 +51,7 @@ public:
   unsigned char *get_row(int y);
   void erase();
   void make_geom(int top, int left, float advance, float poly_margin,
+                 float tex_x_size, float tex_y_size,
                  float font_pixels_per_unit, float tex_pixels_per_unit);
 
   DynamicTextPage *_page;