font = GLFont(0, 0, 0, 0);
}
#endif
+
+
+
+// new font code ripped from ZeroRadiant (not in use yet)
+
+#include <pango/pangoft2.h>
+#include "igl.h"
+
+class GLFontInternal
+{
+ const char *font_string;
+ int font_height;
+ int font_ascent;
+ int font_descent;
+ int y_offset_bitmap_render_pango_units;
+ PangoContext *ft2_context;
+
+ public:
+ GLFontInternal(const char *_font_string): font_string(font_string)
+ {
+ PangoFontDescription *font_desc;
+ PangoLayout *layout;
+ PangoRectangle log_rect;
+ int font_ascent_pango_units;
+ int font_descent_pango_units;
+
+ // This call is deprecated so we'll have to fix it sometime.
+ ft2_context = pango_ft2_get_context(72, 72);
+
+ font_desc = pango_font_description_from_string(font_string);
+ pango_context_set_font_description(ft2_context, font_desc);
+ pango_font_description_free(font_desc);
+
+ layout = pango_layout_new(ft2_context);
+#if !PANGO_VERSION_CHECK(1,22,0)
+ PangoLayoutIter *iter;
+ iter = pango_layout_get_iter(layout);
+ font_ascent_pango_units = pango_layout_iter_get_baseline(iter);
+ pango_layout_iter_free(iter);
+#else
+ font_ascent_pango_units = pango_layout_get_baseline(layout);
+#endif
+ pango_layout_get_extents(layout, NULL, &log_rect);
+ g_object_unref(G_OBJECT(layout));
+ font_descent_pango_units = log_rect.height - font_ascent_pango_units;
+
+ font_ascent = PANGO_PIXELS_CEIL(font_ascent_pango_units);
+ font_descent = PANGO_PIXELS_CEIL(font_descent_pango_units);
+ font_height = font_ascent + font_descent;
+ y_offset_bitmap_render_pango_units = (font_ascent * PANGO_SCALE) - font_ascent_pango_units;
+ }
+
+ ~GLFontInternal()
+ {
+ g_object_unref(G_OBJECT(ft2_context));
+ }
+
+ // Renders the input text at the current location with the current color.
+ // The X position of the current location is used to place the left edge of the text image,
+ // where the text image bounds are defined as the logical extents of the line of text.
+ // The Y position of the current location is used to place the bottom of the text image.
+ // You should offset the Y position by the amount returned by gtk_glwidget_font_descent()
+ // if you want to place the baseline of the text image at the current Y position.
+ // Note: A problem with this function is that if the lower left corner of the text falls
+ // just a hair outside of the viewport (meaning the current raster position is invalid),
+ // then no text will be rendered. The solution to this is a very hacky one. You can search
+ // Google for "glDrawPixels clipping".
+ void printString(const char *s)
+ {
+ // The idea for this code initially came from the font-pangoft2.c example that comes with GtkGLExt.
+
+ PangoLayout *layout;
+ PangoRectangle log_rect;
+ FT_Bitmap bitmap;
+ unsigned char *begin_bitmap_buffer;
+ GLfloat color[4];
+ GLint previous_unpack_alignment;
+ GLboolean previous_blend_enabled;
+ GLint previous_blend_func_src;
+ GLint previous_blend_func_dst;
+ GLfloat previous_red_bias;
+ GLfloat previous_green_bias;
+ GLfloat previous_blue_bias;
+ GLfloat previous_alpha_scale;
+
+ layout = pango_layout_new(ft2_context);
+ pango_layout_set_width(layout, -1); // -1 no wrapping. All text on one line.
+ pango_layout_set_text(layout, s, -1); // -1 null-terminated string.
+ pango_layout_get_extents(layout, NULL, &log_rect);
+
+ if (log_rect.width > 0 && log_rect.height > 0) {
+ bitmap.rows = font_ascent + font_descent;
+ bitmap.width = PANGO_PIXELS_CEIL(log_rect.width);
+ bitmap.pitch = -bitmap.width; // Rendering it "upside down" for OpenGL.
+ begin_bitmap_buffer = (unsigned char *) g_malloc(bitmap.rows * bitmap.width);
+ memset(begin_bitmap_buffer, 0, bitmap.rows * bitmap.width);
+ bitmap.buffer = begin_bitmap_buffer + (bitmap.rows - 1) * bitmap.width; // See pitch above.
+ bitmap.num_grays = 0xff;
+ bitmap.pixel_mode = FT_PIXEL_MODE_GRAY;
+ pango_ft2_render_layout_subpixel(&bitmap, layout, -log_rect.x,
+ y_offset_bitmap_render_pango_units);
+ GlobalOpenGL().m_glGetFloatv(GL_CURRENT_COLOR, color);
+
+ // Save state. I didn't see any OpenGL push/pop operations for these.
+ // Question: Is saving/restoring this state necessary? Being safe.
+ GlobalOpenGL().m_glGetIntegerv(GL_UNPACK_ALIGNMENT, &previous_unpack_alignment);
+ previous_blend_enabled = GlobalOpenGL().m_glIsEnabled(GL_BLEND);
+ GlobalOpenGL().m_glGetIntegerv(GL_BLEND_SRC, &previous_blend_func_src);
+ GlobalOpenGL().m_glGetIntegerv(GL_BLEND_DST, &previous_blend_func_dst);
+ GlobalOpenGL().m_glGetFloatv(GL_RED_BIAS, &previous_red_bias);
+ GlobalOpenGL().m_glGetFloatv(GL_GREEN_BIAS, &previous_green_bias);
+ GlobalOpenGL().m_glGetFloatv(GL_BLUE_BIAS, &previous_blue_bias);
+ GlobalOpenGL().m_glGetFloatv(GL_ALPHA_SCALE, &previous_alpha_scale);
+
+ GlobalOpenGL().m_glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ GlobalOpenGL().m_glEnable(GL_BLEND);
+ GlobalOpenGL().m_glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+ GlobalOpenGL().m_glPixelTransferf(GL_RED_BIAS, color[0]);
+ GlobalOpenGL().m_glPixelTransferf(GL_GREEN_BIAS, color[1]);
+ GlobalOpenGL().m_glPixelTransferf(GL_BLUE_BIAS, color[2]);
+ GlobalOpenGL().m_glPixelTransferf(GL_ALPHA_SCALE, color[3]);
+
+ GlobalOpenGL().m_glDrawPixels(bitmap.width, bitmap.rows,
+ GL_ALPHA, GL_UNSIGNED_BYTE, begin_bitmap_buffer);
+ g_free(begin_bitmap_buffer);
+
+ // Restore state in reverse order of how we set it.
+ GlobalOpenGL().m_glPixelTransferf(GL_ALPHA_SCALE, previous_alpha_scale);
+ GlobalOpenGL().m_glPixelTransferf(GL_BLUE_BIAS, previous_blue_bias);
+ GlobalOpenGL().m_glPixelTransferf(GL_GREEN_BIAS, previous_green_bias);
+ GlobalOpenGL().m_glPixelTransferf(GL_RED_BIAS, previous_red_bias);
+ GlobalOpenGL().m_glBlendFunc(previous_blend_func_src, previous_blend_func_dst);
+ if (!previous_blend_enabled) { GlobalOpenGL().m_glDisable(GL_BLEND); }
+ GlobalOpenGL().m_glPixelStorei(GL_UNPACK_ALIGNMENT, previous_unpack_alignment);
+ }
+
+ g_object_unref(G_OBJECT(layout));
+ }
+};