Load textures in a single frame

Because of texture sharing, Qt3D compares functor before executing them.
Instead of blindly loading a TextureImage functor which could turn out to not
be used, Qt3D required 2 frames to fully update a texture. This behavior has
been removed, now when a texture image functor is updated, it updates the
texture in one frame. It is assumed that the user is responsible for declaring
only TextureImage that he is actually going to use.

Any scene that uses OnDemand rendering and frequently changes a texture image
functor can be used to test this. (ex-painted-cube is a good example for KDAB)
or paintedtexture-cpp in manual tests

Change-Id: I8c2f13876244a862633e10e472e2b49cbd6e126b
Task-number: QTBUG-63561
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

1 files changed, 2 insertions, 5 deletions

diff --git a/src/render/graphicshelpers/graphicscontext.cpp b/src/render/graphicshelpers/graphicscontext.cpp
index d742865c4..7fa112b12 100644
--- a/src/render/graphicshelpers/graphicscontext.cpp
+++ b/src/render/graphicshelpers/graphicscontext.cpp
@@ -1205,7 +1205,6 @@ bool GraphicsContext::setParameters(ShaderParameterPack &parameterPack)
 {
     // Activate textures and update TextureUniform in the pack
     // with the correct textureUnit
-    bool allValid = true;
 
     // Set the pinned texture of the previous material texture
     // to pinable so that we should easily find an available texture unit
@@ -1225,10 +1224,8 @@ bool GraphicsContext::setParameters(ShaderParameterPack &parameterPack)
                 Q_ASSERT(texUniform.valueType() == UniformValue::TextureValue);
                 const int texUnit = activateTexture(TextureScopeMaterial, t);
                 texUniform.data<int>()[namedTex.uniformArrayIndex] = texUnit;
-                // if the texture data from generators may not be available yet,
-                // make sure that the next frame is rendered
                 if (texUnit == -1)
-                    allValid = false;
+                    return false;
             }
         }
     }
@@ -1283,7 +1280,7 @@ bool GraphicsContext::setParameters(ShaderParameterPack &parameterPack)
         applyUniform(uniform, v);
     }
     // if not all data is valid, the next frame will be rendered immediately
-    return allValid;
+    return true;
 }
 
 void GraphicsContext::readBuffer(GLenum mode)