enforce trilinear and mipmap generation

rendering/framebufferobject.cpp

@@ -26,37 +26,39 @@ void FramebufferObject::Create(QOpenGLContext *ctx, int width, int height)
   // set context to new context provided
   ctx_ = ctx;
 
+  QOpenGLFunctions* f = ctx->functions();
+
   // create framebuffer object
-  ctx->functions()->glGenFramebuffers(1, &buffer_);
+  f->glGenFramebuffers(1, &buffer_);
 
   // create texture
-  ctx->functions()->glGenTextures(1, &texture_);
+  f->glGenTextures(1, &texture_);
 
   // bind framebuffer for attaching
-  ctx->functions()->glBindFramebuffer(GL_DRAW_FRAMEBUFFER, buffer_);
+  f->glBindFramebuffer(GL_DRAW_FRAMEBUFFER, buffer_);
 
   // bind texture
-  ctx->functions()->glBindTexture(GL_TEXTURE_2D, texture_);
+  f->glBindTexture(GL_TEXTURE_2D, texture_);
 
   // allocate storage for texture
-  ctx->functions()->glTexImage2D(
+  f->glTexImage2D(
         GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr
         );
 
   // set texture filtering to bilinear
-  ctx->functions()->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-  ctx->functions()->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+  f->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+  f->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 
   // attach texture to framebuffer
-  ctx->functions()->glFramebufferTexture2D(
+  f->glFramebufferTexture2D(
         GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture_, 0
         );
 
   // release texture
-  ctx->functions()->glBindTexture(GL_TEXTURE_2D, 0);
+  f->glBindTexture(GL_TEXTURE_2D, 0);
 
   // release framebuffer
-  ctx->functions()->glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
+  f->glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
 }
 
 void FramebufferObject::Destroy()