Autogenerate mipmaps for textures

Generate mipmaps if they are missing using QT3DS_GENERATE_MIPMAPS.
Also enable anisotropic filtering and allow setting the value with
QT3DS_ANISOTROPIC_VALUE env variable.

Change-Id: I53f7ed6ec0e3ee511b4d605ba8a76d1177ced966
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>

5 files changed, 23 insertions, 3 deletions

diff --git a/src/Runtime/Source/render/Qt3DSRenderTextureBase.cpp b/src/Runtime/Source/render/Qt3DSRenderTextureBase.cpp
index d055d72c..c1c3e97d 100644
--- a/src/Runtime/Source/render/Qt3DSRenderTextureBase.cpp
+++ b/src/Runtime/Source/render/Qt3DSRenderTextureBase.cpp
@@ -136,6 +136,12 @@ namespace render {
         }
     }
 
+    static GLfloat getMaxAnisotropy()
+    {
+        static GLfloat val = (GLfloat)qEnvironmentVariableIntValue("QT3DS_ANISOTROPIC_VALUE");
+        return val > 0 ? val : 1.0f;
+    }
+
     void NVRenderTextureBase::applyTexParams()
     {
         if (m_SamplerParamsDirty) {
@@ -143,7 +149,8 @@ namespace render {
                                      m_Sampler->m_MinFilter, m_Sampler->m_MagFilter,
                                      m_Sampler->m_WrapS, m_Sampler->m_WrapT, m_Sampler->m_WrapR,
                                      m_Sampler->m_MinLod, m_Sampler->m_MaxLod, m_Sampler->m_LodBias,
-                                     m_Sampler->m_CompareMode, m_Sampler->m_CompareOp);
+                                     m_Sampler->m_CompareMode, m_Sampler->m_CompareOp,
+                                     getMaxAnisotropy());
 
             m_SamplerParamsDirty = false;
         }
diff --git a/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGL3.cpp b/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGL3.cpp
index d78c51d9..f49f3a16 100644
--- a/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGL3.cpp
+++ b/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGL3.cpp
@@ -300,7 +300,8 @@ namespace render {
                                    m_Conversion.fromTextureCompareFuncToGL(compareFunc)));
 
         if (m_backendSupport.caps.bits.bAnistropySupported) {
-            GL_CALL_EXTRA_FUNCTION(glTexParameterf(glTarget, GL_TEXTURE_MAX_ANISOTROPY_EXT, anisotropy));
+            GL_CALL_EXTRA_FUNCTION(glTexParameterf(glTarget, GL_TEXTURE_MAX_ANISOTROPY_EXT,
+                                                   qMin(anisotropy, m_maxAnisotropy)));
         }
     }
 
diff --git a/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGLBase.cpp b/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGLBase.cpp
index 940ab094..ba25ae7e 100644
--- a/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGLBase.cpp
+++ b/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGLBase.cpp
@@ -81,6 +81,8 @@ namespace render {
             QT3DS_NEW(m_Foundation.getAllocator(), NVRenderBackendRasterizerStateGL)();
         m_pCurrentDepthStencilState =
             QT3DS_NEW(m_Foundation.getAllocator(), NVRenderBackendDepthStencilStateGL)();
+
+        m_glFunctions->glGetFloatv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &m_maxAnisotropy);
     }
     /// destructor
     NVRenderBackendGLBase::~NVRenderBackendGLBase()
@@ -1167,7 +1169,8 @@ namespace render {
         GL_CALL_FUNCTION(glTexParameteri(glTarget, GL_TEXTURE_WRAP_T,
                                    m_Conversion.fromTextureCoordOpToGL(wrapT)));
         if (m_backendSupport.caps.bits.bAnistropySupported) {
-            GL_CALL_FUNCTION(glTexParameterf(glTarget, GL_TEXTURE_MAX_ANISOTROPY_EXT, anisotropy));
+            GL_CALL_FUNCTION(glTexParameterf(glTarget, GL_TEXTURE_MAX_ANISOTROPY_EXT,
+                                             qMin(m_maxAnisotropy, anisotropy)));
         }
     }
 
diff --git a/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGLBase.h b/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGLBase.h
index 9048a9c4..28e4dbb1 100644
--- a/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGLBase.h
+++ b/src/Runtime/Source/render/backends/gl/Qt3DSRenderBackendGLBase.h
@@ -523,6 +523,7 @@ namespace render {
 #endif
         QOpenGLFunctions *m_glFunctions;
         QOpenGLExtraFunctions *m_glExtraFunctions;
+        GLfloat m_maxAnisotropy;
     };
 }
 }
diff --git a/src/Runtime/Source/runtimerender/resourcemanager/Qt3DSRenderBufferManager.cpp b/src/Runtime/Source/runtimerender/resourcemanager/Qt3DSRenderBufferManager.cpp
index 74e55d79..638e8458 100644
--- a/src/Runtime/Source/runtimerender/resourcemanager/Qt3DSRenderBufferManager.cpp
+++ b/src/Runtime/Source/runtimerender/resourcemanager/Qt3DSRenderBufferManager.cpp
@@ -446,6 +446,14 @@ struct SBufferManager : public IBufferManager
                 theTexture->SetTextureData(
                     NVDataRef<QT3DSU8>((QT3DSU8 *)inLoadedImage.data, inLoadedImage.dataSizeInBytes), 0,
                     inLoadedImage.width, inLoadedImage.height, inLoadedImage.format, destFormat);
+                {
+                    static int enable = qEnvironmentVariableIntValue("QT3DS_GENERATE_MIPMAPS");
+                    if (enable) {
+                        theTexture->SetMinFilter(NVRenderTextureMinifyingOp::LinearMipmapLinear);
+                        theTexture->SetMagFilter(NVRenderTextureMagnifyingOp::Linear);
+                        theTexture->GenerateMipmaps();
+                    }
+                }
             }
 
             if (inBsdfMipmaps