wrapper for different sized output

Former-commit-id: 621dd6f28ac87e2f78be707eacea1cd33a112fec

include/igl/opengl/glfw/map_texture.cpp

@@ -20,6 +20,27 @@ IGL_INLINE bool igl::opengl::glfw::map_texture(
   const int h,
   const int nc,
   std::vector<unsigned char> & out_data)
+{
+  int out_w = w;
+  int out_h = h;
+  int out_nc = nc;
+  return map_texture(_V,_F,_U,in_data,w,h,nc,out_data,out_w,out_h,out_nc);
+}
+
+  
+template <typename DerivedV, typename DerivedF, typename DerivedU>
+IGL_INLINE bool igl::opengl::glfw::map_texture(
+  const Eigen::MatrixBase<DerivedV> & _V,
+  const Eigen::MatrixBase<DerivedF> & _F,
+  const Eigen::MatrixBase<DerivedU> & _U,
+  const unsigned char * in_data,
+  const int w,
+  const int h,
+  const int nc,
+  std::vector<unsigned char> & out_data,
+  int & out_w,
+  int & out_h,
+  int & out_nc)
 {
   const auto fail = [](const std::string msg)
   {
@@ -43,6 +64,7 @@ IGL_INLINE bool igl::opengl::glfw::map_texture(
     DerivedF::RowsAtCompileTime,
     DerivedF::ColsAtCompileTime,
     Eigen::RowMajor> F = _F.template cast<int>();
+  const int dim = U.cols();
   // Set up glfw
   if(!glfwInit()) fail("Could not initialize glfw");
   glfwSetErrorCallback([](int id,const char* m){std::cerr<<m<<std::endl;});
@@ -56,7 +78,8 @@ IGL_INLINE bool igl::opengl::glfw::map_texture(
   if(!window) fail("Could not create glfw window");
   glfwMakeContextCurrent(window);
   // Compile each shader
-  std::string vertex_shader = R"(
+  std::string vertex_shader = dim == 2 ? 
+    R"(
 #version 330 core
 layout(location = 0) in vec2 position;
 layout(location = 1) in vec2 tex_coord_v;
@@ -66,7 +89,20 @@ void main()
   tex_coord_f = vec2(tex_coord_v.x,1.-tex_coord_v.y);
   gl_Position = vec4( 2.*position.x-1., 2.*(1.-position.y)-1., 0.,1.);
 }
-)";
+)"
+    :
+    R"(
+#version 330 core
+layout(location = 0) in vec3 position;
+layout(location = 1) in vec2 tex_coord_v;
+out vec2 tex_coord_f;
+void main()
+{
+  tex_coord_f = vec2(tex_coord_v.x,1.-tex_coord_v.y);
+  gl_Position = vec4( 2.*position.x-1., 2.*(1.-position.y)-1., position.z,1.);
+}
+)"
+    ;
   std::string fragment_shader = R"(
 #version 330 core
 layout(location = 0) out vec3 color;
@@ -93,7 +129,7 @@ void main()
   glEnableVertexAttribArray(0);
   glBindBuffer(GL_ARRAY_BUFFER,vbo);
   glBufferData(GL_ARRAY_BUFFER, sizeof(double)*U.size(), U.data(), GL_STATIC_DRAW);
-  glVertexAttribLPointer(0, U.cols(), GL_DOUBLE, V.cols() * sizeof(GLdouble), (GLvoid*)0);
+  glVertexAttribLPointer(0, U.cols(), GL_DOUBLE, U.cols() * sizeof(GLdouble), (GLvoid*)0);
   glGenBuffers(1,&tbo);
   glEnableVertexAttribArray(1);
   glBindBuffer(GL_ARRAY_BUFFER,tbo);
@@ -124,7 +160,8 @@ void main()
   glGenTextures(1, &out_tex);
   glBindTexture(GL_TEXTURE_2D, out_tex);
   // always use float for internal storage
-  glTexImage2D(GL_TEXTURE_2D, 0,GL_RGB, w, h, 0,GL_RGB, GL_FLOAT, 0);
+  assert(out_nc == 3);
+  glTexImage2D(GL_TEXTURE_2D, 0,GL_RGB, out_w, out_h, 0,GL_RGB, GL_FLOAT, 0);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
   glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, out_tex, 0);
@@ -140,7 +177,7 @@ void main()
   // clear screen and set viewport
   glClearColor(0.0,1.0,0.0,0.);
   glClear(GL_COLOR_BUFFER_BIT);
-  glViewport(0,0,w,h);
+  glViewport(0,0,out_w,out_h);
   // Attach shader program
   glUseProgram(prog_id);
   glActiveTexture(GL_TEXTURE0 + 0);
@@ -151,7 +188,8 @@ void main()
   glDrawElements(GL_TRIANGLES, F.size(), GL_UNSIGNED_INT, 0);
   glBindVertexArray(0);
   // Write into memory
-  out_data.resize(nc*w*h);
+  assert(out_nc == 3);
+  out_data.resize(out_nc*out_w*out_h);
   glBindTexture(GL_TEXTURE_2D, out_tex);
   glGetTexImage(GL_TEXTURE_2D, 0, format, GL_UNSIGNED_BYTE, &out_data[0]);
   // OpenGL cleanup

include/igl/opengl/glfw/map_texture.h

@@ -35,6 +35,19 @@ namespace igl
         const int h,
         const int nc,
         std::vector<unsigned char> & out_data);
+      template <typename DerivedV, typename DerivedF, typename DerivedU>
+      IGL_INLINE bool map_texture(
+        const Eigen::MatrixBase<DerivedV> & _V,
+        const Eigen::MatrixBase<DerivedF> & _F,
+        const Eigen::MatrixBase<DerivedU> & _U,
+        const unsigned char * in_data,
+        const int w,
+        const int h,
+        const int nc,
+        std::vector<unsigned char> & out_data,
+        int & out_w,
+        int & out_h,
+        int & out_nc);
     }
   }
 }