From 6abffceb43f3a701697503cdd20a82dcea1e7b10 Mon Sep 17 00:00:00 2001
From: Olivier Prat <olivier@zvork.fr>
Date: Tue, 16 Oct 2018 09:39:32 +0200
Subject: [PATCH] Mip generation texture slot is higher and doesn't interfere
 anymore

---
 .../src/gpu/gl/GLBackendTexture.cpp           |  9 +++++++--
 libraries/gpu/src/gpu/Batch.cpp               |  2 --
 libraries/gpu/src/gpu/MipGeneration.slh       | 20 +++++++++++++++++++
 libraries/gpu/src/gpu/ShaderConstants.h       |  2 +-
 4 files changed, 28 insertions(+), 5 deletions(-)
 create mode 100644 libraries/gpu/src/gpu/MipGeneration.slh

diff --git a/libraries/gpu-gl-common/src/gpu/gl/GLBackendTexture.cpp b/libraries/gpu-gl-common/src/gpu/gl/GLBackendTexture.cpp
index f4f2da3ee5..b74ff079d7 100644
--- a/libraries/gpu-gl-common/src/gpu/gl/GLBackendTexture.cpp
+++ b/libraries/gpu-gl-common/src/gpu/gl/GLBackendTexture.cpp
@@ -86,9 +86,14 @@ void GLBackend::do_generateTextureMipsWithPipeline(const Batch& batch, size_t pa
         return;
     }
 
-    // Do not transfer the texture, this call is expected for rendering texture
+    // Always make sure the GLObject is in sync
     GLTexture* object = syncGPUObject(resourceTexture);
-    if (!object) {
+    if (object) {
+        GLuint to = object->_texture;
+        glActiveTexture(GL_TEXTURE0 + gpu::slot::texture::MipCreationInput);
+        glBindTexture(object->_target, to);
+        (void)CHECK_GL_ERROR();
+    } else {
         return;
     }
 
diff --git a/libraries/gpu/src/gpu/Batch.cpp b/libraries/gpu/src/gpu/Batch.cpp
index 4cf678f26e..0e5fc1404f 100644
--- a/libraries/gpu/src/gpu/Batch.cpp
+++ b/libraries/gpu/src/gpu/Batch.cpp
@@ -418,8 +418,6 @@ void Batch::generateTextureMips(const TexturePointer& texture) {
 }
 
 void Batch::generateTextureMipsWithPipeline(const TexturePointer& texture, int numMips) {
-    setResourceTexture(gpu::slot::texture::MipCreationInput, texture);
-
     ADD_COMMAND(generateTextureMipsWithPipeline);
 
     _params.emplace_back(_textures.cache(texture));
diff --git a/libraries/gpu/src/gpu/MipGeneration.slh b/libraries/gpu/src/gpu/MipGeneration.slh
new file mode 100644
index 0000000000..bc8dd39042
--- /dev/null
+++ b/libraries/gpu/src/gpu/MipGeneration.slh
@@ -0,0 +1,20 @@
+<!
+//  MipGeneration.slh
+//  libraries/gpu/src
+//
+//  Created by Olivier Prat on 10/16/18.
+//  Copyright 2018 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+!>
+<@if not MIP_GENERATION_SLH@>
+<@def MIP_GENERATION_SLH@>
+
+<@include gpu/ShaderConstants.h@>
+
+layout(binding=GPU_TEXTURE_MIP_CREATION_INPUT) uniform sampler2D texMap;
+
+in vec2 varTexCoord0;
+
+<@endif@>
\ No newline at end of file
diff --git a/libraries/gpu/src/gpu/ShaderConstants.h b/libraries/gpu/src/gpu/ShaderConstants.h
index 426c64e913..0724b4eb40 100644
--- a/libraries/gpu/src/gpu/ShaderConstants.h
+++ b/libraries/gpu/src/gpu/ShaderConstants.h
@@ -22,7 +22,7 @@
 #define GPU_TEXTURE_TRANSFORM_OBJECT 31
 
 // Mip creation
-#define GPU_TEXTURE_MIP_CREATION_INPUT 0
+#define GPU_TEXTURE_MIP_CREATION_INPUT 30
 
 #define GPU_STORAGE_TRANSFORM_OBJECT 7