4 files changed, 9 insertions, 1 deletions
diff --git a/drivers/gles2/rasterizer_canvas_gles2.cpp b/drivers/gles2/rasterizer_canvas_gles2.cpp
index 3d388c031a..d6fbf04353 100644
--- a/drivers/gles2/rasterizer_canvas_gles2.cpp
+++ b/drivers/gles2/rasterizer_canvas_gles2.cpp
@@ -75,6 +75,7 @@ void RasterizerCanvasGLES2::canvas_begin() {
 	}
 
 	if (storage->frame.clear_request) {
+		glColorMask(true, true, true, true);
 		glClearColor(storage->frame.clear_request_color.r,
 				storage->frame.clear_request_color.g,
 				storage->frame.clear_request_color.b,
diff --git a/drivers/gles2/rasterizer_gles2.cpp b/drivers/gles2/rasterizer_gles2.cpp
index a1a0b9e2c6..73d93f7b46 100644
--- a/drivers/gles2/rasterizer_gles2.cpp
+++ b/drivers/gles2/rasterizer_gles2.cpp
@@ -392,6 +392,12 @@ void RasterizerGLES2::end_frame(bool p_swap_buffers) {
 		OS::get_singleton()->swap_buffers();
 	else
 		glFinish();
+
+	if (p_swap_buffers) {
+		glColorMask(true, true, true, true);
+		glClearColor(0, 0, 0, 1);
+		glClear(GL_COLOR_BUFFER_BIT);
+	}
 }
 
 void RasterizerGLES2::finalize() {
diff --git a/drivers/gles2/rasterizer_storage_gles2.cpp b/drivers/gles2/rasterizer_storage_gles2.cpp
index 1bd3c0a935..6ff6bd7ced 100644
--- a/drivers/gles2/rasterizer_storage_gles2.cpp
+++ b/drivers/gles2/rasterizer_storage_gles2.cpp
@@ -3641,6 +3641,7 @@ void RasterizerStorageGLES2::_render_target_allocate(RenderTarget *rt) {
 
 	texture_set_flags(rt->texture, texture->flags);
 
+	glClearColor(0, 0, 0, 0);
 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
 	// copy texscreen buffers
diff --git a/drivers/gles2/shaders/scene.glsl b/drivers/gles2/shaders/scene.glsl
index 9251e21080..3e64c92e96 100644
--- a/drivers/gles2/shaders/scene.glsl
+++ b/drivers/gles2/shaders/scene.glsl
@@ -526,7 +526,7 @@ FRAGMENT_SHADER_CODE
 
 #if defined(ENABLE_NORMALMAP)
 	normalmap.xy = normalmap.xy * 2.0 - 1.0;
-	normalmap.z = sqrt(1.0 - dot(normalmap.xy, normalmap.xy));
+	normalmap.z = sqrt(max(0.0, 1.0 - dot(normalmap.xy, normalmap.xy)));
 
 	// normal = normalize(mix(normal_interp, tangent * normalmap.x + binormal * normalmap.y + normal * normalmap.z, normaldepth)) * side;
 	normal = normalmap;