kwineffects: Rename generateShaderFromResources() to generateShaderFromFile()

It works both with resource files and normal files.

src/effects/invert/invert.cpp

@@ -71,7 +71,7 @@ bool InvertEffect::loadData()
     ensureResources();
     m_inited = true;
 
-    m_shader = ShaderManager::instance()->generateShaderFromResources(ShaderTrait::MapTexture, QString(), QStringLiteral(":/effects/invert/shaders/invert.frag"));
+    m_shader = ShaderManager::instance()->generateShaderFromFile(ShaderTrait::MapTexture, QString(), QStringLiteral(":/effects/invert/shaders/invert.frag"));
     if (!m_shader->isValid()) {
         qCCritical(KWIN_INVERT) << "The shader failed to load!";
         return false;

src/effects/lookingglass/lookingglass.cpp

@@ -114,7 +114,7 @@ bool LookingGlassEffect::loadData()
         return false;
     }
 
-    m_shader = ShaderManager::instance()->generateShaderFromResources(ShaderTrait::MapTexture, QString(), QStringLiteral(":/effects/lookingglass/shaders/lookingglass.frag"));
+    m_shader = ShaderManager::instance()->generateShaderFromFile(ShaderTrait::MapTexture, QString(), QStringLiteral(":/effects/lookingglass/shaders/lookingglass.frag"));
     if (m_shader->isValid()) {
         ShaderBinder binder(m_shader);
         m_shader->setUniform("u_textureSize", QVector2D(screenSize.width(), screenSize.height()));

src/effects/startupfeedback/startupfeedback.cpp

@@ -152,7 +152,7 @@ void StartupFeedbackEffect::reconfigure(Effect::ReconfigureFlags flags)
         m_type = BlinkingFeedback;
         if (effects->compositingType() == OpenGLCompositing) {
             ensureResources();
-            m_blinkingShader.reset(ShaderManager::instance()->generateShaderFromResources(ShaderTrait::MapTexture, QString(), QStringLiteral(":/effects/startupfeedback/shaders/blinking-startup.frag")));
+            m_blinkingShader.reset(ShaderManager::instance()->generateShaderFromFile(ShaderTrait::MapTexture, QString(), QStringLiteral(":/effects/startupfeedback/shaders/blinking-startup.frag")));
             if (m_blinkingShader->isValid()) {
                 qCDebug(KWIN_STARTUPFEEDBACK) << "Blinking Shader is valid";
             } else {

src/libkwineffects/kwinglutils.cpp

@@ -800,7 +800,7 @@ static QString resolveShaderFilePath(const QString &filePath)
     return prefix + suffix + extension;
 }
 
-GLShader *ShaderManager::generateShaderFromResources(ShaderTraits traits, const QString &vertexFile, const QString &fragmentFile)
+GLShader *ShaderManager::generateShaderFromFile(ShaderTraits traits, const QString &vertexFile, const QString &fragmentFile)
 {
     auto loadShaderFile = [](const QString &filePath) {
         QFile file(filePath);

src/libkwineffects/kwinglutils.h

@@ -262,9 +262,6 @@ public:
 
     /**
      * Creates a custom shader with the given @p traits and custom @p vertexFile and or @p fragmentFile.
-     * The file names specified in @p vertexFile and @p fragmentFile are relative paths to the shaders
-     * resource file shipped together with KWin. This means this method can only be used for built-in
-     * effects, for 3rd party effects generateCustomShader should be used.
      *
      * If the @p vertexFile is empty a vertex shader with the given @p traits is generated.
      * If it is not empty the @p vertexFile is used as the source for the vertex shader.
@@ -274,14 +271,16 @@ public:
      * So if both @p vertexFile and @p fragmentFile are provided the @p traits are ignored.
      * If neither are provided a new shader following the @p traits is generated.
      *
+     * If a custom shader stage is provided and core profile is used, the final file path will
+     * be resolved by appending "_core" to the basename.
+     *
      * @param traits The shader traits for generating the shader
      * @param vertexFile optional vertex shader source code to be used instead of shader traits
      * @param fragmentFile optional fragment shader source code to be used instead of shader traits
      * @return new generated shader
      * @see generateCustomShader
-     * @since 5.6
      */
-    GLShader *generateShaderFromResources(ShaderTraits traits, const QString &vertexFile = QString(), const QString &fragmentFile = QString());
+    GLShader *generateShaderFromFile(ShaderTraits traits, const QString &vertexFile = QString(), const QString &fragmentFile = QString());
 
     /**
      * @return a pointer to the ShaderManager instance