[grits] Add GritsTester for debugging GritsObjects

[Andy Spencer <andys src gnome org>]

commit dccc3b445b3c67322eb4f071df46bff02fac89ed
Author: Andy Spencer <andy753421 gmail com>
Date:   Mon Jan 24 03:33:30 2011 +0000

    Add GritsTester for debugging GritsObjects
    
    The "tester" object is similar to a stripped down version of
    GisOpenGL/GisViewer. It is intended for debugging GisObjects during
    development. It displays one or more objects centered in the view and
    and supports panning/moving around to inspect various parts of the
    object.

 examples/tester.c |  209 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 examples/tester.h |   56 ++++++++++++++
 2 files changed, 265 insertions(+), 0 deletions(-)
---
diff --git a/examples/tester.c b/examples/tester.c
new file mode 100644
index 0000000..22032ee
--- /dev/null
+++ b/examples/tester.c
@@ -0,0 +1,209 @@
+/*
+ * Copyright (C) 2009-2010 Andy Spencer <andy753421 gmail com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <gtk/gtk.h>
+#include <gtk/gtkgl.h>
+#include <gdk/gdkkeysyms.h>
+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <stdlib.h>
+#include <math.h>
+
+#include "tester.h"
+
+/*************
+ * Callbacks *
+ *************/
+static gboolean on_expose(GritsTester *tester, GdkEventExpose *event, gpointer _)
+{
+	g_debug("GritsTester: on_expose");
+
+	glClearColor(0.0, 0.0, 0.0, 0.0);
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+	glClearDepth(1.0);
+	glEnable(GL_BLEND);
+
+	glEnable(GL_DEPTH_TEST);
+	glDepthFunc(GL_LEQUAL);
+	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+	//glDisable(GL_DEPTH_TEST);
+	//glBlendFunc(GL_SRC_ALPHA, GL_ONE);
+
+	/* Lighting */
+	glMatrixMode(GL_MODELVIEW);
+	glPushMatrix();
+	glLoadIdentity();
+	float light_ambient[]  = {0.1f, 0.1f, 0.1f, 1.0f};
+	float light_diffuse[]  = {0.6f, 0.6f, 0.8f, 1.0f};
+	float light_position[] = {-40.0f, 80.0f, 40.0f, 1.0f};
+	glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
+	glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
+	glLightfv(GL_LIGHT0, GL_POSITION, light_position);
+	glEnable(GL_COLOR_MATERIAL);
+	glEnable(GL_LIGHTING);
+	glEnable(GL_LIGHT0);
+	glPopMatrix();
+
+	glColor4f(1.0f, 1.0f, 1.0f, 0.5f);
+
+	/* Draw */
+	gdk_gl_draw_cube(FALSE, 2);
+	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+	for (GList *cur = tester->objects; cur; cur = cur->next)
+		grits_object_draw(cur->data, NULL);
+	if (tester->wireframe) {
+		glDisable(GL_LIGHTING);
+		glEnable(GL_POLYGON_OFFSET_LINE);
+		glPolygonOffset(-1,0);
+		glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
+		for (GList *cur = tester->objects; cur; cur = cur->next)
+			grits_object_draw(cur->data, NULL);
+	}
+
+	/* Flush */
+	GdkGLDrawable *gldrawable = gdk_gl_drawable_get_current();
+	gdk_gl_drawable_swap_buffers(gldrawable);
+	return FALSE;
+}
+
+static gboolean on_key_press(GritsTester *tester, GdkEventKey *event, gpointer _)
+{
+	g_debug("GritsTester: on_key_press");
+	guint kv = event->keyval;
+	gdouble model[16];
+	glGetDoublev(GL_MODELVIEW_MATRIX, model);
+
+	glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+	     if (kv == GDK_q) gtk_main_quit();
+        else if (kv == GDK_w) tester->wireframe = !tester->wireframe;
+	else if (kv == GDK_h) glTranslated( 0.1,  0,  0);
+	else if (kv == GDK_l) glTranslated(-0.1,  0,  0);
+	else if (kv == GDK_j) glTranslated( 0,  0.1,  0);
+	else if (kv == GDK_k) glTranslated( 0, -0.1,  0);
+	else if (kv == GDK_i) glTranslated( 0,  0,  0.1);
+	else if (kv == GDK_o) glTranslated( 0,  0, -0.1);
+	else if (kv == GDK_H) glRotated(-5, 0,1,0);
+	else if (kv == GDK_L) glRotated( 5, 0,1,0);
+	else if (kv == GDK_J) glRotated( 5, 1,0,0);
+	else if (kv == GDK_K) glRotated(-5, 1,0,0);
+	else if (kv == GDK_I) glRotated(-5, 0,0,1);
+	else if (kv == GDK_O) glRotated( 5, 0,0,1);
+	glMultMatrixd(model);
+
+	gtk_widget_queue_draw(GTK_WIDGET(tester));
+	return FALSE;
+}
+
+static gboolean on_configure(GritsTester *tester, GdkEventConfigure *event, gpointer _)
+{
+	g_debug("GritsTester: on_configure");
+
+	double width  = GTK_WIDGET(tester)->allocation.width;
+	double height = GTK_WIDGET(tester)->allocation.height;
+
+	/* Setup OpenGL Window */
+	glViewport(0, 0, width, height);
+	glMatrixMode(GL_PROJECTION);
+	glLoadIdentity();
+	double ang = atan(height/FOV_DIST);
+	gluPerspective(rad2deg(ang)*2, width/height, 0.001, 100);
+
+	return FALSE;
+}
+
+static void on_realize(GritsTester *tester, gpointer _)
+{
+	g_debug("GritsTester: on_realize");
+
+	/* Start OpenGL */
+	GdkGLContext   *glcontext  = gtk_widget_get_gl_context(GTK_WIDGET(tester));
+	GdkGLDrawable  *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(tester));
+	if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext))
+		g_assert_not_reached();
+
+	/* Connect signals and idle functions now that opengl is fully initialized */
+	g_object_set(tester, "can-focus", TRUE, NULL);
+	gtk_widget_add_events(GTK_WIDGET(tester), GDK_KEY_PRESS_MASK);
+	g_signal_connect(tester, "configure-event", G_CALLBACK(on_configure), NULL);
+	g_signal_connect(tester, "expose-event",    G_CALLBACK(on_expose),    NULL);
+	g_signal_connect(tester, "key-press-event", G_CALLBACK(on_key_press), NULL);
+
+	/* Re-queue resize incase configure was triggered before realize */
+	gtk_widget_queue_resize(GTK_WIDGET(tester));
+
+	/* Setup model view matrix */
+	glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+	glTranslated(0, 0, -2);
+}
+
+/***********
+ * Methods *
+ ***********/
+gpointer grits_tester_add(GritsTester *tester, GritsObject *object)
+{
+	g_debug("GritsTester: add");
+	gtk_widget_queue_draw(GTK_WIDGET(tester));
+	object->viewer = (void*)tester;
+	return tester->objects = g_list_prepend(tester->objects, object);
+}
+
+GritsObject *grits_tester_remove(GritsTester *tester, gpointer _ref)
+{
+	g_debug("GritsTester: remove");
+	GList *ref = _ref;
+	GritsObject *object = ref->data;
+	tester->objects = g_list_remove_link(tester->objects, ref);
+	return object;
+}
+
+GritsTester *grits_tester_new()
+{
+	g_debug("GritsTester: new");
+	GritsTester *tester = g_object_new(GRITS_TYPE_TESTER, NULL);
+	return tester;
+}
+
+/****************
+ * GObject code *
+ ****************/
+G_DEFINE_TYPE(GritsTester, grits_tester, GTK_TYPE_DRAWING_AREA);
+static void grits_tester_init(GritsTester *tester)
+{
+	g_debug("GritsTester: init");
+	tester->objects = NULL;
+
+	/* Set OpenGL before "realize" */
+	GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
+			GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
+			GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
+	if (!glconfig)
+		g_error("Failed to create glconfig");
+	if (!gtk_widget_set_gl_capability(GTK_WIDGET(tester),
+				glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
+		g_error("GL lacks required capabilities");
+	g_object_unref(glconfig);
+
+	/* Finish OpenGL init after it's realized */
+	g_signal_connect(tester, "realize", G_CALLBACK(on_realize), NULL);
+}
+static void grits_tester_class_init(GritsTesterClass *klass)
+{
+	g_debug("GritsTester: class_init");
+}
diff --git a/examples/tester.h b/examples/tester.h
new file mode 100644
index 0000000..74d84aa
--- /dev/null
+++ b/examples/tester.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2009-2010 Andy Spencer <andy753421 gmail com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PUReOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GRITS_TESTER_H__
+#define __GRITS_TESTER_H__
+
+#include <gtk/gtk.h>
+#include <glib-object.h>
+
+#include <objects/grits-object.h>
+
+/* Type macros */
+#define GRITS_TYPE_TESTER            (grits_tester_get_type())
+#define GRITS_TESTER(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj),   GRITS_TYPE_TESTER, GritsTester))
+#define GRITS_IS_TESTER(obj)         (G_TYPE_CHECK_INSTANCE_TYPE((obj),   GRITS_TYPE_TESTER))
+#define GRITS_TESTER_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST   ((klass), GRITS_TYPE_TESTER, GritsTesterClass))
+#define GRITS_IS_TESTER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE   ((klass), GRITS_TYPE_TESTER))
+#define GRITS_TESTER_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj),   GRITS_TYPE_TESTER, GritsTesterClass))
+
+typedef struct _GritsTester      GritsTester;
+typedef struct _GritsTesterClass GritsTesterClass;
+
+struct _GritsTester {
+	GtkDrawingArea parent_instance;
+
+	/* instance members */
+	gboolean  wireframe;
+	GList    *objects;
+};
+
+struct _GritsTesterClass {
+	GtkDrawingAreaClass parent_class;
+};
+
+GType grits_tester_get_type(void);
+
+/* Methods */
+GritsTester *grits_tester_new();
+gpointer grits_tester_add(GritsTester *tester, GritsObject *object);
+GritsObject *grits_tester_remove(GritsTester *tester, gpointer ref);
+
+#endif