Reduce uniform copies

Change-Id: I322e97d9d0da185a98ced5e782a801b3474a892a
Reviewed-by: Mike Krus <mike.krus@kdab.com>
(cherry picked from commit 897b6cd5de7042edcdaf610f80d97d2b422c73c2)

2 files changed, 29 insertions, 11 deletions

diff --git a/src/plugins/renderers/opengl/graphicshelpers/submissioncontext.cpp b/src/plugins/renderers/opengl/graphicshelpers/submissioncontext.cpp
index 95f4758ba..34f31f23f 100644
--- a/src/plugins/renderers/opengl/graphicshelpers/submissioncontext.cpp
+++ b/src/plugins/renderers/opengl/graphicshelpers/submissioncontext.cpp
@@ -1270,21 +1270,20 @@ bool SubmissionContext::setParameters(ShaderParameterPack &parameterPack, GLShad
     }
 
     // Update uniforms in the Default Uniform Block
-    const PackUniformHash values = parameterPack.uniforms();
-    const QVector<int> &activeUniformsIndices = parameterPack.submissionUniformIndices();
+    const PackUniformHash& values = parameterPack.uniforms();
+    const auto &activeUniformsIndices = parameterPack.submissionUniformIndices();
     const QVector<ShaderUniform> &shaderUniforms = shader->uniforms();
 
     for (const int shaderUniformIndex : activeUniformsIndices) {
         const ShaderUniform &uniform = shaderUniforms[shaderUniformIndex];
-        const UniformValue &v = values.value(uniform.m_nameId);
+        values.apply(uniform.m_nameId, [&] (const UniformValue& v) {
+            // skip invalid textures/images
+            if (!((v.valueType() == UniformValue::TextureValue ||
+                   v.valueType() == UniformValue::ShaderImageValue) &&
+                  *v.constData<int>() == -1))
+                applyUniform(uniform, v);
+        });
 
-        // skip invalid textures/images
-        if ((v.valueType() == UniformValue::TextureValue ||
-             v.valueType() == UniformValue::ShaderImageValue) &&
-            *v.constData<int>() == -1)
-            continue;
-
-        applyUniform(uniform, v);
     }
     // if not all data is valid, the next frame will be rendered immediately
     return true;
diff --git a/src/plugins/renderers/opengl/renderer/shaderparameterpack_p.h b/src/plugins/renderers/opengl/renderer/shaderparameterpack_p.h
index 2ed80ef2a..78cb8515f 100644
--- a/src/plugins/renderers/opengl/renderer/shaderparameterpack_p.h
+++ b/src/plugins/renderers/opengl/renderer/shaderparameterpack_p.h
@@ -116,6 +116,17 @@ struct PackUniformHash
         }
     }
 
+    void insert(int key, UniformValue &&value)
+    {
+        const int idx = keys.indexOf(key);
+        if (idx != -1) {
+            values[idx] = std::move(value);
+        } else {
+            keys.push_back(key);
+            values.push_back(std::move(value));
+        }
+    }
+
     UniformValue value(int key) const
     {
         const int idx = keys.indexOf(key);
@@ -133,13 +144,21 @@ struct PackUniformHash
         return value(key);
     }
 
+    template<typename F>
+    void apply(int key, F func) const noexcept
+    {
+        const int idx = keys.indexOf(key);
+        if (idx != -1)
+            func(values[idx]);
+    }
+
     void erase(int idx)
     {
         keys.removeAt(idx);
         values.removeAt(idx);
     }
 
-    bool contains(int key) const
+    bool contains(int key) const noexcept
     {
         return keys.contains(key);
     }