// Name: isosurf.cpp
// Purpose: wxGLCanvas demo program
// Author: Brian Paul (original gltk version), Wolfram Gloger
-// Modified by: Julian Smart
+// Modified by: Julian Smart, Francesco Montorsi
// Created: 04/01/98
// RCS-ID: $Id$
// Copyright: (c) Julian Smart
-// Licence: wxWindows licence
+// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
-#ifdef __GNUG__
-#pragma implementation
-#pragma interface
-#endif
-
// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"
#endif
#if !wxUSE_GLCANVAS
-#error Please set wxUSE_GLCANVAS to 1 in setup.h.
+ #error "OpenGL required: set wxUSE_GLCANVAS to 1 and rebuild the library"
#endif
#include "wx/timer.h"
#include "wx/glcanvas.h"
-
-#include <GL/gl.h>
-#include <GL/glu.h>
+#include "wx/math.h"
+#include "wx/log.h"
+#include "wx/cmdline.h"
+#include "wx/wfstream.h"
+#include "wx/zstream.h"
+#include "wx/txtstrm.h"
#include "isosurf.h"
+#include "../../sample.xpm"
-// The following part is taken largely unchanged from the original C Version
-
-#include <math.h>
-
-GLboolean speed_test = GL_FALSE;
-GLboolean use_vertex_arrays = GL_FALSE;
-GLboolean doubleBuffer = GL_TRUE;
+// global options which can be set through command-line options
+GLboolean g_use_vertex_arrays = GL_FALSE;
+GLboolean g_doubleBuffer = GL_TRUE;
+GLboolean g_smooth = GL_TRUE;
+GLboolean g_lighting = GL_TRUE;
-GLboolean smooth = GL_TRUE;
-GLboolean lighting = GL_TRUE;
-#define MAXVERTS 10000
-
-static GLfloat verts[MAXVERTS][3];
-static GLfloat norms[MAXVERTS][3];
-static GLint numverts;
-
-static GLfloat xrot;
-static GLfloat yrot;
+//---------------------------------------------------------------------------
+// MyApp
+//---------------------------------------------------------------------------
+IMPLEMENT_APP(MyApp)
-static void read_surface( char *filename )
+bool MyApp::OnInit()
{
- FILE *f;
-
- f = fopen(filename,"r");
- if (!f) {
- wxString msg("Couldn't read ");
- msg += filename;
- wxMessageBox(msg);
- return;
- }
-
- numverts = 0;
- while (!feof(f) && numverts<MAXVERTS) {
- fscanf( f, "%f %f %f %f %f %f",
- &verts[numverts][0], &verts[numverts][1], &verts[numverts][2],
- &norms[numverts][0], &norms[numverts][1], &norms[numverts][2] );
- numverts++;
- }
- numverts--;
-
- printf("%d vertices, %d triangles\n", numverts, numverts-2);
- fclose(f);
-}
+ if ( !wxApp::OnInit() )
+ return false;
+ // Create the main frame window
+ MyFrame *frame = new MyFrame(NULL, wxT("wxWidgets OpenGL Isosurf Sample"));
-static void draw_surface( void )
-{
- GLint i;
-
-#ifdef GL_EXT_vertex_array
- if (use_vertex_arrays) {
- glDrawArraysEXT( GL_TRIANGLE_STRIP, 0, numverts );
- }
- else {
-#endif
- glBegin( GL_TRIANGLE_STRIP );
- for (i=0;i<numverts;i++) {
- glNormal3fv( norms[i] );
- glVertex3fv( verts[i] );
- }
- glEnd();
-#ifdef GL_EXT_vertex_array
- }
-#endif
+ return true;
}
-
-static void draw1(void)
+void MyApp::OnInitCmdLine(wxCmdLineParser& parser)
{
- glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
- glPushMatrix();
- glRotatef( yrot, 0.0, 1.0, 0.0 );
- glRotatef( xrot, 1.0, 0.0, 0.0 );
-
- draw_surface();
+ parser.AddSwitch("", "sb", "Do not use double buffering");
+ parser.AddSwitch("", "db", "Use double buffering");
+ parser.AddSwitch("", "va", "Use vertex arrays");
- glPopMatrix();
-
- glFlush();
+ wxApp::OnInitCmdLine(parser);
}
-
-static void InitMaterials(void)
+bool MyApp::OnCmdLineParsed(wxCmdLineParser& parser)
{
- static float ambient[] = {0.1, 0.1, 0.1, 1.0};
- static float diffuse[] = {0.5, 1.0, 1.0, 1.0};
- static float position0[] = {0.0, 0.0, 20.0, 0.0};
- static float position1[] = {0.0, 0.0, -20.0, 0.0};
- static float front_mat_shininess[] = {60.0};
- static float front_mat_specular[] = {0.2, 0.2, 0.2, 1.0};
- static float front_mat_diffuse[] = {0.5, 0.28, 0.38, 1.0};
- /*
- static float back_mat_shininess[] = {60.0};
- static float back_mat_specular[] = {0.5, 0.5, 0.2, 1.0};
- static float back_mat_diffuse[] = {1.0, 1.0, 0.2, 1.0};
- */
- static float lmodel_ambient[] = {1.0, 1.0, 1.0, 1.0};
- static float lmodel_twoside[] = {GL_FALSE};
+ if (parser.Found("sb"))
+ g_doubleBuffer = GL_FALSE;
+ else if (parser.Found("db"))
+ g_doubleBuffer = GL_TRUE;
- glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
- glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);
- glLightfv(GL_LIGHT0, GL_POSITION, position0);
- glEnable(GL_LIGHT0);
-
- glLightfv(GL_LIGHT1, GL_AMBIENT, ambient);
- glLightfv(GL_LIGHT1, GL_DIFFUSE, diffuse);
- glLightfv(GL_LIGHT1, GL_POSITION, position1);
- glEnable(GL_LIGHT1);
-
- glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
- glLightModelfv(GL_LIGHT_MODEL_TWO_SIDE, lmodel_twoside);
- glEnable(GL_LIGHTING);
+ if (parser.Found("va"))
+ g_use_vertex_arrays = GL_TRUE;
- glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, front_mat_shininess);
- glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, front_mat_specular);
- glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, front_mat_diffuse);
+ return wxApp::OnCmdLineParsed(parser);
}
+//---------------------------------------------------------------------------
+// MyFrame
+//---------------------------------------------------------------------------
-static void Init(void)
-{
- glClearColor(0.0, 0.0, 0.0, 0.0);
-
- glShadeModel(GL_SMOOTH);
- glEnable(GL_DEPTH_TEST);
-
- InitMaterials();
-
- glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- glFrustum( -1.0, 1.0, -1.0, 1.0, 5, 25 );
-
- glMatrixMode(GL_MODELVIEW);
- glLoadIdentity();
- glTranslatef( 0.0, 0.0, -6.0 );
-
-#ifdef GL_EXT_vertex_array
- if (use_vertex_arrays) {
- glVertexPointerEXT( 3, GL_FLOAT, 0, numverts, verts );
- glNormalPointerEXT( GL_FLOAT, 0, numverts, norms );
- glEnable( GL_VERTEX_ARRAY_EXT );
- glEnable( GL_NORMAL_ARRAY_EXT );
- }
-#endif
-}
-
-
-static void Reshape(int width, int height)
-{
- glViewport(0, 0, (GLint)width, (GLint)height);
-}
-
-
-static GLenum Args(int argc, char **argv)
-{
- GLint i;
-
- for (i = 1; i < argc; i++) {
- if (strcmp(argv[i], "-sb") == 0) {
- doubleBuffer = GL_FALSE;
- }
- else if (strcmp(argv[i], "-db") == 0) {
- doubleBuffer = GL_TRUE;
- }
- else if (strcmp(argv[i], "-speed") == 0) {
- speed_test = GL_TRUE;
- doubleBuffer = GL_TRUE;
- }
- else if (strcmp(argv[i], "-va") == 0) {
- use_vertex_arrays = GL_TRUE;
- }
- else {
- wxString msg("Bad option: ");
- msg += argv[i];
- wxMessageBox(msg);
- return GL_FALSE;
- }
- }
-
- return GL_TRUE;
-}
-
-// The following part was written for wxWindows 1.66
-MyFrame *frame = NULL;
-
-IMPLEMENT_APP(MyApp)
+BEGIN_EVENT_TABLE(MyFrame, wxFrame)
+ EVT_MENU(wxID_EXIT, MyFrame::OnExit)
+END_EVENT_TABLE()
-// `Main program' equivalent, creating windows and returning main app frame
-bool MyApp::OnInit(void)
+MyFrame::MyFrame(wxFrame *frame, const wxString& title, const wxPoint& pos,
+ const wxSize& size, long style)
+ : wxFrame(frame, wxID_ANY, title, pos, size, style),
+ m_canvas(NULL)
{
- Args(argc, argv);
+ SetIcon(wxICON(sample));
- // Create the main frame window
- frame = new MyFrame(NULL, "Isosurf GL Sample", wxPoint(50, 50), wxSize(200, 200));
- // Give it an icon
- frame->SetIcon(wxIcon("mondrian"));
+ // Make a menubar
+ wxMenu *fileMenu = new wxMenu;
- // Make a menubar
- wxMenu *fileMenu = new wxMenu;
+ fileMenu->Append(wxID_EXIT, wxT("E&xit"));
+ wxMenuBar *menuBar = new wxMenuBar;
+ menuBar->Append(fileMenu, wxT("&File"));
+ SetMenuBar(menuBar);
- fileMenu->Append(wxID_EXIT, "E&xit");
- wxMenuBar *menuBar = new wxMenuBar;
- menuBar->Append(fileMenu, "&File");
- frame->SetMenuBar(menuBar);
// Make a TestGLCanvas
// JACS
#ifdef __WXMSW__
- int *gl_attrib = NULL;
+ int *gl_attrib = NULL;
#else
- int gl_attrib[20] = { WX_GL_RGBA, WX_GL_MIN_RED, 1, WX_GL_MIN_GREEN, 1,
- WX_GL_MIN_BLUE, 1, WX_GL_DEPTH_SIZE, 1,
- WX_GL_DOUBLEBUFFER, None };
+ int gl_attrib[20] =
+ { WX_GL_RGBA, WX_GL_MIN_RED, 1, WX_GL_MIN_GREEN, 1,
+ WX_GL_MIN_BLUE, 1, WX_GL_DEPTH_SIZE, 1,
+ WX_GL_DOUBLEBUFFER,
+# if defined(__WXMAC__) || defined(__WXCOCOA__)
+ GL_NONE };
+# else
+ None };
+# endif
#endif
- if(!doubleBuffer)
- {
- printf("don't have double buffer, disabling\n");
+ if (!g_doubleBuffer)
+ {
+ wxLogWarning("Disabling double buffering");
+
#ifdef __WXGTK__
- gl_attrib[9] = None;
+ gl_attrib[9] = None;
#endif
- doubleBuffer = GL_FALSE;
- }
-
- frame->m_canvas = new TestGLCanvas(frame, -1, wxPoint(0, 0), wxSize(200, 200),
- 0, "TestGLCanvas", gl_attrib );
-
- // Show the frame
- frame->Show(TRUE);
-
- frame->m_canvas->SetCurrent();
- read_surface( "isosurf.dat" );
+ g_doubleBuffer = GL_FALSE;
+ }
- Init();
+ // Show the frame
+ Show(true);
- return TRUE;
+ m_canvas = new TestGLCanvas(this, wxID_ANY, gl_attrib);
}
-BEGIN_EVENT_TABLE(MyFrame, wxFrame)
- EVT_MENU(wxID_EXIT, MyFrame::OnExit)
-END_EVENT_TABLE()
-
-// My frame constructor
-MyFrame::MyFrame(wxFrame *frame, const wxString& title, const wxPoint& pos,
- const wxSize& size, long style):
- wxFrame(frame, -1, title, pos, size, style)
+MyFrame::~MyFrame()
{
- m_canvas = NULL;
+ delete m_canvas;
}
// Intercept menu commands
-void MyFrame::OnExit(wxCommandEvent& event)
+void MyFrame::OnExit( wxCommandEvent& WXUNUSED(event) )
{
- Destroy();
+ // true is to force the frame to close
+ Close(true);
}
-/*
- * TestGLCanvas implementation
- */
+
+//---------------------------------------------------------------------------
+// TestGLCanvas
+//---------------------------------------------------------------------------
BEGIN_EVENT_TABLE(TestGLCanvas, wxGLCanvas)
EVT_SIZE(TestGLCanvas::OnSize)
EVT_PAINT(TestGLCanvas::OnPaint)
EVT_CHAR(TestGLCanvas::OnChar)
EVT_MOUSE_EVENTS(TestGLCanvas::OnMouseEvent)
- EVT_ERASE_BACKGROUND(TestGLCanvas::OnEraseBackground)
END_EVENT_TABLE()
-TestGLCanvas::TestGLCanvas(wxWindow *parent, wxWindowID id,
- const wxPoint& pos, const wxSize& size, long style, const wxString& name, int* gl_attrib):
- wxGLCanvas(parent, id, pos, size, style, name, gl_attrib)
+TestGLCanvas::TestGLCanvas(wxWindow *parent,
+ wxWindowID id,
+ int* gl_attrib)
+ : wxGLCanvas(parent, id, gl_attrib)
{
- parent->Show(TRUE);
- SetCurrent();
-
- /* Make sure server supports the vertex array extension */
- char* extensions = (char *) glGetString( GL_EXTENSIONS );
- if (!extensions || !strstr( extensions, "GL_EXT_vertex_array" )) {
- use_vertex_arrays = GL_FALSE;
- }
+ m_xrot = 0;
+ m_yrot = 0;
+ m_numverts = 0;
+
+ // Explicitly create a new rendering context instance for this canvas.
+ m_glRC = new wxGLContext(this);
+
+ // Make the new context current (activate it for use) with this canvas.
+ SetCurrent(*m_glRC);
+
+ InitGL();
+ InitMaterials();
+ LoadSurface("isosurf.dat.gz");
}
+TestGLCanvas::~TestGLCanvas()
+{
+ delete m_glRC;
+}
-TestGLCanvas::~TestGLCanvas(void)
+void TestGLCanvas::LoadSurface(const wxString& filename)
{
+ // FIXME
+ // we need to set english locale to force wxTextInputStream's calls to
+ // wxStrtod to use the point and not the comma as decimal separator...
+ // (the isosurf.dat contains points and not commas)...
+ wxLocale l(wxLANGUAGE_ENGLISH);
+
+ wxZlibInputStream* stream =
+ new wxZlibInputStream(new wxFFileInputStream(filename));
+ if (!stream || !stream->IsOk())
+ {
+ wxLogError("Cannot load '%s' type of files!", filename.c_str());
+ delete stream;
+ return;
+ }
+
+ {
+ // we suppose to have in input a text file containing floating numbers
+ // space/newline-separed... first 3 numbers are the coordinates of a
+ // vertex and the following 3 are the relative vertex normal and so on...
+
+ wxTextInputStream inFile(*stream);
+ m_numverts = 0;
+
+ while (!stream->Eof() && m_numverts < MAXVERTS)// && m_numverts<MAXVERTS)
+ {
+ inFile >> m_verts[m_numverts][0] >> m_verts[m_numverts][1] >> m_verts[m_numverts][2];
+ inFile >> m_norms[m_numverts][0] >> m_norms[m_numverts][1] >> m_norms[m_numverts][2];
+
+ m_numverts++;
+ }
+
+ // discard last vertex; it is a zero caused by the EOF
+ m_numverts--;
+ }
+
+ delete stream;
+
+ wxLogMessage(wxT("Loaded %d vertices, %d triangles from '%s'"),
+ m_numverts, m_numverts-2, filename.c_str());
+
+ // NOTE: for some reason under wxGTK the following is required to avoid that
+ // the surface gets rendered in a small rectangle in the top-left corner of the frame
+ PostSizeEventToParent();
}
-void TestGLCanvas::OnPaint( wxPaintEvent& event )
+void TestGLCanvas::OnPaint( wxPaintEvent& WXUNUSED(event) )
{
// This is a dummy, to avoid an endless succession of paint messages.
// OnPaint handlers must always create a wxPaintDC.
wxPaintDC dc(this);
-#ifndef __WXMOTIF__
- if (!GetContext()) return;
-#endif
+ // This is normally only necessary if there is more than one wxGLCanvas
+ // or more than one wxGLContext in the application.
+ SetCurrent(*m_glRC);
+
+ glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
+ glPushMatrix();
+ glRotatef( m_yrot, 0.0f, 1.0f, 0.0f );
+ glRotatef( m_xrot, 1.0f, 0.0f, 0.0f );
+
+ // draw the surface
+ if (g_use_vertex_arrays)
+ {
+ glDrawArrays( GL_TRIANGLE_STRIP, 0, m_numverts );
+ }
+ else
+ {
+ glBegin( GL_TRIANGLE_STRIP );
+
+ for (int i=0;i<m_numverts;i++)
+ {
+ glNormal3fv( m_norms[i] );
+ glVertex3fv( m_verts[i] );
+ }
+
+ glEnd();
+ }
- SetCurrent();
+ glPopMatrix();
+ glFlush(); // Not really necessary: buffer swapping below implies glFlush()
- draw1();
SwapBuffers();
}
void TestGLCanvas::OnSize(wxSizeEvent& event)
{
-#ifndef __WXMOTIF__
- if (!GetContext()) return;
-#endif
-
- SetCurrent();
- int width, height;
- GetClientSize(& width, & height);
- Reshape(width, height);
+ // This is normally only necessary if there is more than one wxGLCanvas
+ // or more than one wxGLContext in the application.
+ SetCurrent(*m_glRC);
+
+ // It's up to the application code to update the OpenGL viewport settings.
+ // This is OK here only because there is only one canvas that uses the
+ // context. See the cube sample for that case that multiple canvases are
+ // made current with one context.
+ glViewport(0, 0, event.GetSize().x, event.GetSize().y);
}
void TestGLCanvas::OnChar(wxKeyEvent& event)
{
- switch(event.KeyCode()) {
+ switch( event.GetKeyCode() )
+ {
case WXK_ESCAPE:
- exit(0);
+ wxTheApp->ExitMainLoop();
+ return;
+
case WXK_LEFT:
- yrot -= 15.0;
- break;
+ m_yrot -= 15.0;
+ break;
+
case WXK_RIGHT:
- yrot += 15.0;
- break;
+ m_yrot += 15.0;
+ break;
+
case WXK_UP:
- xrot += 15.0;
- break;
+ m_xrot += 15.0;
+ break;
+
case WXK_DOWN:
- xrot -= 15.0;
- break;
+ m_xrot -= 15.0;
+ break;
+
case 's': case 'S':
- smooth = !smooth;
- if (smooth) {
- glShadeModel(GL_SMOOTH);
- } else {
- glShadeModel(GL_FLAT);
- }
- break;
+ g_smooth = !g_smooth;
+ if (g_smooth)
+ glShadeModel(GL_SMOOTH);
+ else
+ glShadeModel(GL_FLAT);
+ break;
+
case 'l': case 'L':
- lighting = !lighting;
- if (lighting) {
- glEnable(GL_LIGHTING);
- } else {
- glDisable(GL_LIGHTING);
- }
- break;
- default:
- {
+ g_lighting = !g_lighting;
+ if (g_lighting)
+ glEnable(GL_LIGHTING);
+ else
+ glDisable(GL_LIGHTING);
+ break;
+
+ default:
event.Skip();
- return;
- }
+ return;
}
- Refresh(FALSE);
+ Refresh(false);
}
void TestGLCanvas::OnMouseEvent(wxMouseEvent& event)
static int dragging = 0;
static float last_x, last_y;
- //printf("%f %f %d\n", event.GetX(), event.GetY(), (int)event.LeftIsDown());
- if(event.LeftIsDown()) {
- if(!dragging) {
- dragging = 1;
- } else {
- yrot += (event.GetX() - last_x)*1.0;
- xrot += (event.GetY() - last_y)*1.0;
- Refresh(FALSE);
- }
- last_x = event.GetX();
- last_y = event.GetY();
- } else
- dragging = 0;
+ // Allow default processing to happen, or else the canvas cannot gain focus
+ // (for key events).
+ event.Skip();
+
+ if (event.LeftIsDown())
+ {
+ if (!dragging)
+ {
+ dragging = 1;
+ }
+ else
+ {
+ m_yrot += (event.GetX() - last_x)*1.0;
+ m_xrot += (event.GetY() - last_y)*1.0;
+ Refresh(false);
+ }
+ last_x = event.GetX();
+ last_y = event.GetY();
+ }
+ else
+ {
+ dragging = 0;
+ }
}
-void TestGLCanvas::OnEraseBackground(wxEraseEvent& event)
+void TestGLCanvas::InitMaterials()
{
- // Do nothing, to avoid flashing.
+ static const GLfloat ambient[4] = {0.1f, 0.1f, 0.1f, 1.0f};
+ static const GLfloat diffuse[4] = {0.5f, 1.0f, 1.0f, 1.0f};
+ static const GLfloat position0[4] = {0.0f, 0.0f, 20.0f, 0.0f};
+ static const GLfloat position1[4] = {0.0f, 0.0f, -20.0f, 0.0f};
+ static const GLfloat front_mat_shininess[1] = {60.0f};
+ static const GLfloat front_mat_specular[4] = {0.2f, 0.2f, 0.2f, 1.0f};
+ static const GLfloat front_mat_diffuse[4] = {0.5f, 0.28f, 0.38f, 1.0f};
+ /*
+ static const GLfloat back_mat_shininess[1] = {60.0f};
+ static const GLfloat back_mat_specular[4] = {0.5f, 0.5f, 0.2f, 1.0f};
+ static const GLfloat back_mat_diffuse[4] = {1.0f, 1.0f, 0.2f, 1.0f};
+ */
+ static const GLfloat lmodel_ambient[4] = {1.0f, 1.0f, 1.0f, 1.0f};
+ static const GLfloat lmodel_twoside[1] = {GL_FALSE};
+
+ glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
+ glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);
+ glLightfv(GL_LIGHT0, GL_POSITION, position0);
+ glEnable(GL_LIGHT0);
+
+ glLightfv(GL_LIGHT1, GL_AMBIENT, ambient);
+ glLightfv(GL_LIGHT1, GL_DIFFUSE, diffuse);
+ glLightfv(GL_LIGHT1, GL_POSITION, position1);
+ glEnable(GL_LIGHT1);
+
+ glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
+ glLightModelfv(GL_LIGHT_MODEL_TWO_SIDE, lmodel_twoside);
+ glEnable(GL_LIGHTING);
+
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, front_mat_shininess);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, front_mat_specular);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, front_mat_diffuse);
+}
+
+void TestGLCanvas::InitGL()
+{
+ glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+
+ glShadeModel(GL_SMOOTH);
+ glEnable(GL_DEPTH_TEST);
+
+ InitMaterials();
+
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glFrustum( -1.0, 1.0, -1.0, 1.0, 5.0, 25.0 );
+
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glTranslatef( 0.0, 0.0, -6.0 );
+
+ if (g_use_vertex_arrays)
+ {
+ glVertexPointer( 3, GL_FLOAT, 0, m_verts );
+ glNormalPointer( GL_FLOAT, 0, m_norms );
+ glEnable( GL_VERTEX_ARRAY );
+ glEnable( GL_NORMAL_ARRAY );
+ }
}
projects / wxWidgets.git / blobdiff