diff --git a/src/rtt.cpp b/src/rtt.cpp
index 88aee87..d8e7cd7 100644
--- a/src/rtt.cpp
+++ b/src/rtt.cpp
@@ -222,6 +222,7 @@ bool RTT::create(int width, int height, int tex/* = -1*/, GLint internal_format,
 
 void RTT::bindFramebuffer()
 {
+    assert(App::I->is_render_thread());
 #ifdef _DEBUG
     if (bound)
     {
@@ -240,6 +241,7 @@ void RTT::bindFramebuffer()
 
 void RTT::unbindFramebuffer()
 {
+    assert(App::I->is_render_thread());
     if (!bound)
         return;
     glBindFramebuffer(GL_DRAW_FRAMEBUFFER, oldDFboID);
@@ -251,12 +253,14 @@ void RTT::unbindFramebuffer()
 
 void RTT::clear(glm::vec4 color)
 {
+    assert(App::I->is_render_thread());
     glClearColor(color.r, color.g, color.b, color.a);
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 }
 
 void RTT::clear_mask(glm::bool4 mask, glm::vec4 color)
 {
+    assert(App::I->is_render_thread());
     // save old state
     std::array<GLboolean, 4> old_mask;
     glGetBooleanv(GL_COLOR_WRITEMASK, old_mask.data());
@@ -331,11 +335,13 @@ float * RTT::createBufferFloat()
 
 void RTT::bindTexture()
 {
+    assert(App::I->is_render_thread());
     glBindTexture(GL_TEXTURE_2D, texID);
 }
 
 void RTT::unbindTexture()
 {
+    assert(App::I->is_render_thread());
     glBindTexture(GL_TEXTURE_2D, 0);
 }
 
diff --git a/src/texture.cpp b/src/texture.cpp
index 17e517c..f9719a8 100644
--- a/src/texture.cpp
+++ b/src/texture.cpp
@@ -118,11 +118,13 @@ void Texture2D::destroy()
 
 void Texture2D::bind() const
 {
+    assert(App::I->is_render_thread());
     glBindTexture(GL_TEXTURE_2D, m_tex);
 }
 
 void Texture2D::unbind() const
 {
+    assert(App::I->is_render_thread());
     glBindTexture(GL_TEXTURE_2D, 0);
 }
 
@@ -201,21 +203,17 @@ void Sampler::set_border(glm::vec4 rgba)
 }
 void Sampler::bind(int unit) const
 {
-    App::I->render_task([=]
-    {
-        current_unit = unit;
+    assert(App::I->is_render_thread());
+    current_unit = unit;
 #if USE_SAMPLER
-        glBindSampler(unit, id);
+    glBindSampler(unit, id);
 #endif // USE_SAMPLER
-    });
 }
 void Sampler::unbind()
 {
-    App::I->render_task([=]
-    {
+    assert(App::I->is_render_thread());
 #if USE_SAMPLER
-        glBindSampler(current_unit, 0);
+    glBindSampler(current_unit, 0);
 #endif // USE_SAMPLER
-    });
 }