#include "stdafx.h"
#include <gtk/gtkgl.h>
+
+#include <pango/pangoft2.h>
+
#include "glwidget.h"
#include "qgl.h"
return gdk_gl_drawable_gl_begin (gldrawable, glcontext);
}
-GLuint font_list_base;
-static gchar font_string[] = "courier 8";
-static gint font_height;
-void gtk_glwidget_create_font (GtkWidget *widget)
+// Think about rewriting this font stuff to use OpenGL display lists and glBitmap().
+// Bit maps together with display lists may offer a performance increase, but
+// they would not allow antialiased fonts.
+#ifdef _WIN32
+static const char font_string[] = "Courier bold";
+static const int font_height = 9;
+#else
+static const char font_string[] = "Monospace";
+static const int font_height = 10;
+#endif
+static int font_ascent = -1;
+static int font_descent = -1;
+static int y_offset_bitmap_render_pango_units = -1;
+static PangoContext *ft2_context = NULL;
+static int _debug_font_created = 0;
+
+
+// Units are pixels. Returns a positive value [most likely].
+int gtk_glwidget_font_ascent()
{
- PangoFontDescription *font_desc;
- PangoFont *font;
- PangoFontMetrics *font_metrics;
+ if (!_debug_font_created) {
+ Error("Programming error: gtk_glwidget_font_ascent() called but font does not exist; "
+ "you should have called gtk_glwidget_create_font() first");
+ }
- font_list_base = qglGenLists (256);
+ return font_ascent;
+}
- font_desc = pango_font_description_from_string (font_string);
+// Units are pixels. Returns a positive value [most likely].
+int gtk_glwidget_font_descent()
+{
+ if (!_debug_font_created) {
+ Error("Programming error: gtk_glwidget_font_descent() called but font does not exist; "
+ "you should have called gtk_glwidget_create_font() first");
+ }
- font = gdk_gl_font_use_pango_font (font_desc, 0, 256, font_list_base);
+ return font_descent;
+}
- if(font != NULL)
- {
- font_metrics = pango_font_get_metrics (font, NULL);
- font_height = pango_font_metrics_get_ascent (font_metrics) +
- pango_font_metrics_get_descent (font_metrics);
- font_height = PANGO_PIXELS (font_height);
+void gtk_glwidget_create_font()
+{
+ PangoFontDescription *font_desc;
+ PangoLayout *layout;
+ PangoRectangle log_rect;
+ int font_ascent_pango_units;
+ int font_descent_pango_units;
+
+ if (_debug_font_created) {
+ Error("Programming error: gtk_glwidget_create_font() was already called; "
+ "you must call gtk_glwidget_destroy_font() before creating font again");
+ }
+ _debug_font_created = 1;
+
+ // 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_font_description_set_size(font_desc, font_height * PANGO_SCALE);
+ pango_context_set_font_description(ft2_context, font_desc);
+ pango_font_description_free(font_desc);
+
+ layout = pango_layout_new(ft2_context);
+
+ // I don't believe that's standard preprocessor syntax?
+#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);
+ y_offset_bitmap_render_pango_units = (font_ascent * PANGO_SCALE) - font_ascent_pango_units;
+}
- pango_font_metrics_unref (font_metrics);
+void gtk_glwidget_destroy_font()
+{
+ if (!_debug_font_created) {
+ Error("Programming error: gtk_glwidget_destroy_font() called when font "
+ "does not exist");
}
- pango_font_description_free (font_desc);
+ font_ascent = -1;
+ font_descent = -1;
+ y_offset_bitmap_render_pango_units = -1;
+ g_object_unref(G_OBJECT(ft2_context));
+ _debug_font_created = 0;
}
+// 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 gtk_glwidget_print_string(const char *s)
{
- qglListBase(font_list_base);
- qglCallLists(strlen(s), GL_UNSIGNED_BYTE, (unsigned 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;
+
+ if (!_debug_font_created) {
+ Error("Programming error: gtk_glwidget_print_string() called but font does not exist; "
+ "you should have called gtk_glwidget_create_font() first");
+ }
+
+ 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);
+ qglGetFloatv(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.
+ qglGetIntegerv(GL_UNPACK_ALIGNMENT, &previous_unpack_alignment);
+ previous_blend_enabled = qglIsEnabled(GL_BLEND);
+ qglGetIntegerv(GL_BLEND_SRC, &previous_blend_func_src);
+ qglGetIntegerv(GL_BLEND_DST, &previous_blend_func_dst);
+ qglGetFloatv(GL_RED_BIAS, &previous_red_bias);
+ qglGetFloatv(GL_GREEN_BIAS, &previous_green_bias);
+ qglGetFloatv(GL_BLUE_BIAS, &previous_blue_bias);
+ qglGetFloatv(GL_ALPHA_SCALE, &previous_alpha_scale);
+
+ qglPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ qglEnable(GL_BLEND);
+ qglBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+ qglPixelTransferf(GL_RED_BIAS, color[0]);
+ qglPixelTransferf(GL_GREEN_BIAS, color[1]);
+ qglPixelTransferf(GL_BLUE_BIAS, color[2]);
+ qglPixelTransferf(GL_ALPHA_SCALE, color[3]);
+
+ qglDrawPixels(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.
+ qglPixelTransferf(GL_ALPHA_SCALE, previous_alpha_scale);
+ qglPixelTransferf(GL_BLUE_BIAS, previous_blue_bias);
+ qglPixelTransferf(GL_GREEN_BIAS, previous_green_bias);
+ qglPixelTransferf(GL_RED_BIAS, previous_red_bias);
+ qglBlendFunc(previous_blend_func_src, previous_blend_func_dst);
+ if (!previous_blend_enabled) { qglDisable(GL_BLEND); }
+ qglPixelStorei(GL_UNPACK_ALIGNMENT, previous_unpack_alignment);
+ }
+
+ g_object_unref(G_OBJECT(layout));
}
void gtk_glwidget_print_char(char s)
{
- qglListBase(font_list_base);
- qglCallLists(1, GL_UNSIGNED_BYTE, (unsigned char *) &s);
+ char str[2];
+ str[0] = s;
+ str[1] = '\0';
+ gtk_glwidget_print_string(str);
}
-
projects / xonotic / netradiant.git / blobdiff