New Snapshot function (custom resolution)

libsrc/include/incopengl.hpp

@@ -28,6 +28,11 @@
 #define GL_ARRAY_BUFFER                   0x8892
 #define GL_ELEMENT_ARRAY_BUFFER           0x8893
 #define GL_STATIC_DRAW                    0x88E4
+#define GL_FRAMEBUFFER_COMPLETE           0x8CD5
+#define GL_FRAMEBUFFER                    0x8D40
+#define GL_RENDERBUFFER                   0x8D41
+#define GL_DEPTH_ATTACHMENT               0x8D00
+#define GL_COLOR_ATTACHMENT0              0x8CE0
 typedef ptrdiff_t GLintptr;
 typedef ptrdiff_t GLsizeiptr;
 extern void (*glBindBuffer) (GLenum a, GLuint b);
@@ -35,6 +40,18 @@ extern void (*glDeleteBuffers) (GLsizei a, const GLuint *b);
 extern void (*glGenBuffers) (GLsizei a, GLuint *b);
 extern void (*glBufferData) (GLenum a, GLsizeiptr b, const GLvoid *c, GLenum d);
 extern void (*glBufferSubData) (GLenum a, GLintptr b, GLsizeiptr c, const GLvoid *d);
+
+extern GLenum (*glCheckFramebufferStatus) (GLenum target);
+extern void (*glBindFramebuffer) (GLenum target, GLuint framebuffer);
+extern void (*glBindRenderbuffer) (GLenum target, GLuint renderbuffer);
+extern void (*glDeleteFramebuffers) (GLsizei n, const GLuint *framebuffers);
+extern void (*glDeleteRenderbuffers) (GLsizei n, const GLuint *renderbuffers);
+extern void (*glFramebufferTexture) (GLenum target, GLenum attachment, GLuint texture, GLint level);
+extern void (*glGenFramebuffers) (GLsizei n, GLuint *framebuffers);
+extern void (*glGenRenderbuffers) (GLsizei n, GLuint *renderbuffers);
+extern void (*glRenderbufferStorage) (GLenum target, GLenum internalformat, GLsizei width, GLsizei height);
+extern void (*glFramebufferRenderbuffer) (GLenum target, GLenum attachment, GLenum renderbuffertarget, GLuint renderbuffer);
+extern void (*glNamedFramebufferReadBuffer) ( GLuint framebuffer, GLenum mode);
 #endif
 DLL_HEADER void LoadOpenGLFunctionPointers();
 #endif // INCOPENGL_HPP___

libsrc/visualization/mvdraw.cpp

@@ -779,6 +779,64 @@ namespace netgen
     VisualScene::MouseMove(oldx, oldy, newx, newy, mode);
   }
 
+  std::vector<unsigned char> Snapshot( int w, int h )
+  {
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+
+    double pnear = 0.1;
+    double pfar = 10;
+
+    gluPerspective(20.0f, double(w) / h, pnear, pfar);
+
+    glMatrixMode(GL_MODELVIEW);
+
+    GLuint fb = 0;
+    glGenFramebuffers(1, &fb);
+    glBindFramebuffer(GL_FRAMEBUFFER, fb);
+
+    GLuint tex;
+    glGenTextures(1, &tex);
+
+    glBindTexture(GL_TEXTURE_2D, tex);
+
+    glTexImage2D(GL_TEXTURE_2D, 0,GL_RGBA, w, h, 0,GL_RGBA, GL_UNSIGNED_BYTE, 0);
+
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+    GLuint depthrenderbuffer;
+    glGenRenderbuffers(1, &depthrenderbuffer);
+    glBindRenderbuffer(GL_RENDERBUFFER, depthrenderbuffer);
+    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, w, h);
+    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthrenderbuffer);
+
+    glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, tex, 0);
+
+    if(int fbstatus; (fbstatus = glCheckFramebufferStatus(GL_FRAMEBUFFER)) != GL_FRAMEBUFFER_COMPLETE)
+        cerr << "no frame buffer " << fbstatus << endl;
+
+    glBindFramebuffer(GL_FRAMEBUFFER, fb);
+    glViewport(0,0,w,h);
+
+    glPushMatrix();
+    GetVSSolution().DrawScene();
+    glFinish();
+    glPopMatrix();
+
+    std::vector<unsigned char> buffer(w*h*3);
+    glPixelStorei(GL_UNPACK_ALIGNMENT,1);
+    glPixelStorei(GL_PACK_ALIGNMENT,1);
+    glNamedFramebufferReadBuffer( fb, GL_COLOR_ATTACHMENT0 );
+    glReadPixels (0, 0, w, h, GL_RGB, GL_UNSIGNED_BYTE, &buffer[0]);
+
+    glDeleteRenderbuffers(1, &depthrenderbuffer);
+    glDeleteTextures(1, &tex);
+    glDeleteFramebuffers(1, &fb);
+
+    return buffer;
+  }
+
 
 #ifdef PARALLELGL
   void VisualScene :: InitParallelGL ()

libsrc/visualization/mvdraw.hpp

@@ -247,6 +247,7 @@ namespace netgen
                             PointIndex & selpoint2, int & locpi);
 
 
+  DLL_HEADER std::vector<unsigned char> Snapshot( int w, int h );
 }
 
 

libsrc/visualization/vssolution.cpp

@@ -4890,6 +4890,19 @@ void (*glDeleteBuffers) (GLsizei a, const GLuint *b);
 void (*glGenBuffers) (GLsizei a, GLuint *b);
 void (*glBufferData) (GLenum a, GLsizeiptr b, const GLvoid *c, GLenum d);
 void (*glBufferSubData) (GLenum a, GLintptr b, GLsizeiptr c, const GLvoid *d);
+
+GLenum (*glCheckFramebufferStatus) (GLenum target);
+void (*glBindFramebuffer) (GLenum target, GLuint framebuffer);
+void (*glBindRenderbuffer) (GLenum target, GLuint renderbuffer);
+void (*glDeleteFramebuffers) (GLsizei n, const GLuint *framebuffers);
+void (*glDeleteRenderbuffers) (GLsizei n, const GLuint *renderbuffers);
+void (*glFramebufferTexture) (GLenum target, GLenum attachment, GLuint texture, GLint level);
+void (*glGenFramebuffers) (GLsizei n, GLuint *framebuffers);
+void (*glGenRenderbuffers) (GLsizei n, GLuint *renderbuffers);
+void (*glRenderbufferStorage) (GLenum target, GLenum internalformat, GLsizei width, GLsizei height);
+void (*glFramebufferRenderbuffer) (GLenum target, GLenum attachment, GLenum renderbuffertarget, GLuint renderbuffer);
+void (*glNamedFramebufferReadBuffer) ( GLuint framebuffer, GLenum mode);
+
 DLL_HEADER void LoadOpenGLFunctionPointers() {
 #ifdef USE_BUFFERS
   glBindBuffer = (decltype(glBindBuffer)) wglGetProcAddress("glBindBuffer");
@@ -4899,6 +4912,18 @@ DLL_HEADER void LoadOpenGLFunctionPointers() {
   glGenBuffers = (decltype(glGenBuffers)) wglGetProcAddress("glGenBuffers");
   if(!glBindBuffer) throw std::runtime_error("Could not load OpenGL functions!");
 #endif
+
+  glCheckFramebufferStatus = (decltype(glCheckFramebufferStatus )) wglGetProcAddress("glCheckFramebufferStatus");
+  glBindFramebuffer = (decltype(glBindFramebuffer )) wglGetProcAddress("glBindFramebuffer");
+  glBindRenderbuffer = (decltype(glBindRenderbuffer )) wglGetProcAddress("glBindRenderbuffer");
+  glDeleteFramebuffers = (decltype(glDeleteFramebuffers )) wglGetProcAddress("glDeleteFramebuffers");
+  glDeleteRenderbuffers = (decltype(glDeleteRenderbuffers )) wglGetProcAddress("glDeleteRenderbuffers");
+  glFramebufferTexture = (decltype(glFramebufferTexture )) wglGetProcAddress("glFramebufferTexture");
+  glGenFramebuffers = (decltype(glGenFramebuffers )) wglGetProcAddress("glGenFramebuffers");
+  glGenRenderbuffers = (decltype(glGenRenderbuffers )) wglGetProcAddress("glGenRenderbuffers");
+  glRenderbufferStorage = (decltype(glRenderbufferStorage )) wglGetProcAddress("glRenderbufferStorage");
+  glFramebufferRenderbuffer = (decltype(glFramebufferRenderbuffer )) wglGetProcAddress("glFramebufferRenderbuffer");
+  glNamedFramebufferReadBuffer = (decltype(glNamedFramebufferReadBuffer )) wglGetProcAddress("glNamedFramebufferReadBuffer");
 }
 #else  // WIN32
 DLL_HEADER void LoadOpenGLFunctionPointers() { }

ng/netgenpy.cpp

@@ -20,6 +20,10 @@ void DLL_HEADER ExportSTLVis(py::module &m);
 #ifdef OCCGEOMETRY
 void DLL_HEADER ExportNgOCC(py::module &m);
 #endif // OCCGEOMETRY
+namespace netgen
+{
+  std::vector<unsigned char> DLL_HEADER Snapshot( int w, int h );
+}
 
 PYBIND11_MODULE(libngpy, ngpy)
 {
@@ -43,6 +47,7 @@ PYBIND11_MODULE(libngpy, ngpy)
     ExportCSGVis(csgvis);
     py::module stlvis = ngpy.def_submodule("stlvis", "pybind stlvis module");
     ExportSTLVis(stlvis);
+    ngpy.def("Snapshot", netgen::Snapshot);
 #endif // OPENGL
 }
 

python/gui.py

@@ -24,3 +24,16 @@ if not netgen.libngpy._meshing._netgen_executable_started:
         StartGUI()
     except:
         pass
+
+def Snapshot(w,h, filename=None):
+    import ngsolve
+    ngsolve.Redraw(blocking=True)
+    import numpy
+    image = netgen.libngpy.Snapshot(w, h)
+    image = numpy.array(image, dtype=numpy.uint8).reshape(h, w, 3)
+    image = image[::-1,:,:]
+    if filename:
+        import PIL.Image
+        im = PIL.Image.fromarray(image)
+        im.save(filename)
+    return image