Fix for ShaderData

Wasn't using the right index to retrieve the ShaderUniformBlock. Combined with
the use of resize instead of reserve this lead to an unexpected behavior.

Task-number: QTBUG-44874
Change-Id: If66554cf0ea133df33a72a63b256d80a4c4ce823
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

4 files changed, 20 insertions, 7 deletions

diff --git a/src/render/backend/qgraphicshelpergl3.cpp b/src/render/backend/qgraphicshelpergl3.cpp
index 24c2d9d64..cd2a5033b 100644
--- a/src/render/backend/qgraphicshelpergl3.cpp
+++ b/src/render/backend/qgraphicshelpergl3.cpp
@@ -182,7 +182,7 @@ QVector<ShaderUniformBlock> QGraphicsHelperGL3::programUniformBlocks(GLuint prog
     QVector<ShaderUniformBlock> blocks;
     GLint nbrActiveUniformsBlocks = 0;
     m_funcs->glGetProgramiv(programId, GL_ACTIVE_UNIFORM_BLOCKS, &nbrActiveUniformsBlocks);
-    blocks.resize(nbrActiveUniformsBlocks);
+    blocks.reserve(nbrActiveUniformsBlocks);
     for (GLint i = 0; i < nbrActiveUniformsBlocks; i++) {
         QByteArray uniformBlockName(256, '\0');
         ShaderUniformBlock uniformBlock;
diff --git a/src/render/backend/rendershader.cpp b/src/render/backend/rendershader.cpp
index 8d11443da..d4a3cbd70 100644
--- a/src/render/backend/rendershader.cpp
+++ b/src/render/backend/rendershader.cpp
@@ -180,8 +180,19 @@ QHash<QString, ShaderUniform> RenderShader::activeUniformsForBlock(int blockInde
 ShaderUniformBlock RenderShader::uniformBlock(int blockIndex)
 {
     for (int i = 0; i < m_uniformBlocks.size(); ++i) {
-        if (m_uniformBlocks[i].m_index == blockIndex)
+        if (m_uniformBlocks[i].m_index == blockIndex) {
             return m_uniformBlocks[i];
+        }
+    }
+    return ShaderUniformBlock();
+}
+
+ShaderUniformBlock RenderShader::uniformBlock(const QString &blockName)
+{
+    for (int i = 0; i < m_uniformBlocks.size(); ++i) {
+        if (m_uniformBlocks[i].m_name == blockName) {
+            return m_uniformBlocks[i];
+        }
     }
     return ShaderUniformBlock();
 }
@@ -298,7 +309,7 @@ void RenderShader::initializeUniforms(const QVector<ShaderUniform> &uniformsDesc
     for (int i = 0; i < uniformsDescription.size(); i++) {
         m_uniformsNames[i] = uniformsDescription[i].m_name;
         if (uniformsDescription[i].m_blockIndex == -1) { // Uniform is in default block
-            qCDebug(Shaders) << "Active Uniform in Default Block " << uniformsDescription[i].m_name;
+            qCDebug(Shaders) << "Active Uniform in Default Block " << uniformsDescription[i].m_name << uniformsDescription[i].m_blockIndex;
             activeUniformsInDefaultBlock.insert(uniformsDescription[i].m_name, uniformsDescription[i]);
         }
     }
@@ -321,7 +332,7 @@ void RenderShader::initializeUniformBlocks(const QVector<ShaderUniformBlock> &un
     m_uniformBlockNames.resize(uniformBlockDescription.size());
     for (int i = 0; i < uniformBlockDescription.size(); ++i) {
         m_uniformBlockNames[i] = uniformBlockDescription[i].m_name;
-        qCDebug(Shaders) << "Initializing Uniform Block " << m_uniformBlockNames[i];
+        qCDebug(Shaders) << "Initializing Uniform Block {" << m_uniformBlockNames[i] << "}";
 
         // Find all active uniforms for the shader block
         QVector<ShaderUniform>::const_iterator uniformsIt = m_uniforms.begin();
@@ -338,7 +349,7 @@ void RenderShader::initializeUniformBlocks(const QVector<ShaderUniformBlock> &un
                 if (!m_uniformBlockNames[i].isEmpty() && !uniformName.startsWith(m_uniformBlockNames[i]))
                     uniformName = m_uniformBlockNames[i] + QStringLiteral(".") + *uniformNamesIt;
                 activeUniformsInBlock.insert(uniformName, *uniformsIt);
-                qCDebug(Shaders) << "Active Uniform Block " << uniformName << " in block " << m_uniformBlockNames[i];
+                qCDebug(Shaders) << "Active Uniform Block " << uniformName << " in block " << m_uniformBlockNames[i] << " at index " << uniformsIt->m_blockIndex;
             }
             ++uniformsIt;
             ++uniformNamesIt;
diff --git a/src/render/backend/rendershader_p.h b/src/render/backend/rendershader_p.h
index d0a4d1e0e..23d5a8672 100644
--- a/src/render/backend/rendershader_p.h
+++ b/src/render/backend/rendershader_p.h
@@ -84,6 +84,7 @@ public:
 
     QHash<QString, ShaderUniform> activeUniformsForBlock(int blockIndex) const;
     ShaderUniformBlock uniformBlock(int blockIndex);
+    ShaderUniformBlock uniformBlock(const QString &blockName);
 
 private:
     QOpenGLShaderProgram *m_program;
diff --git a/src/render/backend/renderview.cpp b/src/render/backend/renderview.cpp
index 36664515c..6ed9761b8 100644
--- a/src/render/backend/renderview.cpp
+++ b/src/render/backend/renderview.cpp
@@ -616,8 +616,9 @@ void RenderView::setShaderAndUniforms(RenderCommand *command, RenderRenderPass *
                         if (uniformNames.contains(it->name)) { // Parameter is a regular uniform
                             setUniformValue(command->m_uniforms, it->name, it->value);
                             it = parameters.erase(it);
-                        } else if (int idx = uniformBlockNames.indexOf(it->name) != -1) { // Parameter is a uniform block
-                            setUniformBlockValue(command->m_uniforms, shader, shader->uniformBlocks().at(idx), it->value);
+                        } else if (uniformBlockNames.indexOf(it->name) != -1) { // Parameter is a uniform block
+                            const ShaderUniformBlock &block = shader->uniformBlock(it->name);
+                            setUniformBlockValue(command->m_uniforms, shader, block, it->value);
                             it = parameters.erase(it);
                         } else {
                             const QVariant &v = it->value;