Bind ARBBlurShader to OpenGL1

The logic has already ensured that the ARBBlurShader can only be used
when using the OpenGL1 compositor, the OpenGL 2 compositor needs to use
the GLSLBlurShader.

This change moves the complete ARBBlurShader into a KWIN_HAVE_OPENGL_1
ifdef section.

As a side-effect the ::create method can now return a NULL pointer which
makes more sense then returning an ARBBlurShader in case that the
GLSLShader is not supported.

REVIEW: 106738

effects/blur/blur.cpp

@@ -55,7 +55,7 @@ BlurEffect::BlurEffect()
 
     // ### Hackish way to announce support.
     //     Should be included in _NET_SUPPORTED instead.
-    if (shader->isValid() && target->valid()) {
+    if (shader && shader->isValid() && target->valid()) {
         XChangeProperty(display(), rootWindow(), net_wm_blur_region, net_wm_blur_region,
                         32, PropModeReplace, 0, 0);
     } else {
@@ -89,13 +89,14 @@ void BlurEffect::reconfigure(ReconfigureFlags flags)
 
     BlurConfig::self()->readConfig();
     int radius = qBound(2, BlurConfig::blurRadius(), 14);
-    shader->setRadius(radius);
+    if (shader)
+        shader->setRadius(radius);
 
     m_shouldCache = BlurConfig::cacheTexture();
 
     windows.clear();
 
-    if (!shader->isValid())
+    if (!shader || !shader->isValid())
         XDeleteProperty(display(), rootWindow(), net_wm_blur_region);
 }
 
@@ -164,8 +165,12 @@ bool BlurEffect::enabledByDefault()
 
 bool BlurEffect::supported()
 {
-    bool supported = GLRenderTarget::supported() && GLTexture::NPOTTextureSupported() &&
-                     (GLSLBlurShader::supported() || ARBBlurShader::supported());
+    bool supported = GLRenderTarget::supported() && GLTexture::NPOTTextureSupported() && GLSLBlurShader::supported();
+#ifdef KWIN_HAVE_OPENGL_1
+    if (effects->compositingType() == OpenGL1Compositing) {
+        supported = GLRenderTarget::supported() && GLTexture::NPOTTextureSupported() && ARBBlurShader::supported();
+    }
+#endif
 
     if (supported) {
         int maxTexSize;
@@ -262,6 +267,9 @@ void BlurEffect::prePaintWindow(EffectWindow* w, WindowPrePaintData& data, int t
     if (!w->isPaintingEnabled()) {
         return;
     }
+    if (!shader || !shader->isValid()) {
+        return;
+    }
 
     // to blur an area partially we have to shrink the opaque area of a window
     QRegion newClip;
@@ -356,7 +364,7 @@ void BlurEffect::prePaintWindow(EffectWindow* w, WindowPrePaintData& data, int t
 
 bool BlurEffect::shouldBlur(const EffectWindow *w, int mask, const WindowPaintData &data) const
 {
-    if (!target->valid() || !shader->isValid())
+    if (!target->valid() || !shader || !shader->isValid())
         return false;
 
     if (effects->activeFullScreenEffect() && !w->data(WindowForceBlurRole).toBool())
@@ -409,7 +417,7 @@ void BlurEffect::drawWindow(EffectWindow *w, int mask, QRegion region, WindowPai
 void BlurEffect::paintEffectFrame(EffectFrame *frame, QRegion region, double opacity, double frameOpacity)
 {
     const QRect screen(0, 0, displayWidth(), displayHeight());
-    bool valid = target->valid() && shader->isValid();
+    bool valid = target->valid() && shader && shader->isValid();
     QRegion shape = frame->geometry().adjusted(-5, -5, 5, 5) & screen;
     if (valid && !shape.isEmpty() && region.intersects(shape.boundingRect()) && frame->style() != EffectFrameNone) {
         doBlur(shape, screen, opacity * frameOpacity);
@@ -675,6 +683,9 @@ void BlurEffect::doCachedBlur(EffectWindow *w, const QRegion& region, const floa
 
 int BlurEffect::blurRadius() const
 {
+    if (!shader) {
+        return 0;
+    }
     return shader->radius();
 }
 

effects/blur/blurshader.cpp

@@ -47,7 +47,11 @@ BlurShader *BlurShader::create()
     if (GLSLBlurShader::supported())
         return new GLSLBlurShader();
 
+#ifdef KWIN_HAVE_OPENGL_1
     return new ARBBlurShader();
+#else
+    return NULL;
+#endif
 }
 
 void BlurShader::setRadius(int radius)
@@ -299,7 +303,7 @@ void GLSLBlurShader::init()
 // ----------------------------------------------------------------------------
 
 
-
+#ifdef KWIN_HAVE_OPENGL_1
 ARBBlurShader::ARBBlurShader()
     : BlurShader(), program(0)
 {
@@ -312,21 +316,16 @@ ARBBlurShader::~ARBBlurShader()
 
 void ARBBlurShader::reset()
 {
-#ifdef KWIN_HAVE_OPENGL_1
     if (program) {
         glDeleteProgramsARB(1, &program);
         program = 0;
     }
 
     setIsValid(false);
-#endif
 }
 
 bool ARBBlurShader::supported()
 {
-#ifdef KWIN_HAVE_OPENGLES
-    return false;
-#else
     if (!hasGLExtension("GL_ARB_fragment_program"))
         return false;
 
@@ -359,14 +358,10 @@ bool ARBBlurShader::supported()
         return false;
 
     return true;
-#endif
 }
 
 void ARBBlurShader::setPixelDistance(float val)
 {
-#ifdef KWIN_HAVE_OPENGLES
-    Q_UNUSED(val)
-#else
     float firstStep = val * 1.5;
     float nextStep = val * 2.0;
 
@@ -377,37 +372,29 @@ void ARBBlurShader::setPixelDistance(float val)
         glProgramLocalParameter4fARB(GL_FRAGMENT_PROGRAM_ARB, 0, 0, firstStep, 0, 0);
         glProgramLocalParameter4fARB(GL_FRAGMENT_PROGRAM_ARB, 1, 0, nextStep, 0, 0);
     }
-#endif
 }
 
 void ARBBlurShader::bind()
 {
-#ifdef KWIN_HAVE_OPENGL_1
     if (!isValid())
         return;
 
     glEnable(GL_FRAGMENT_PROGRAM_ARB);
     glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, program);
-#endif
 }
 
 void ARBBlurShader::unbind()
 {
-#ifdef KWIN_HAVE_OPENGL_1
     int boundObject;
     glGetProgramivARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_BINDING_ARB, &boundObject);
     if (boundObject == (int)program) {
         glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, 0);
         glDisable(GL_FRAGMENT_PROGRAM_ARB);
     }
-#endif
 }
 
 int ARBBlurShader::maxKernelSize() const
 {
-#ifdef KWIN_HAVE_OPENGLES
-    return 0;
-#else
     int value;
     int result;
 
@@ -418,12 +405,10 @@ int ARBBlurShader::maxKernelSize() const
     result = qMin(result, value / 3); // We need 3 instructions / sample
 
     return result;
-#endif
 }
 
 void ARBBlurShader::init()
 {
-#ifdef KWIN_HAVE_OPENGL_1
     QVector<float> kernel = gaussianKernel();
     const int size = kernel.size();
     const int center = size / 2;
@@ -480,6 +465,6 @@ void ARBBlurShader::init()
         setIsValid(true);
 
     glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, 0);
-#endif
 }
+#endif
 

effects/blur/blurshader.h

@@ -108,7 +108,7 @@ private:
 // ----------------------------------------------------------------------------
 
 
-
+#ifdef KWIN_HAVE_OPENGL_1
 class ARBBlurShader : public BlurShader
 {
 public:
@@ -131,6 +131,7 @@ protected:
 private:
     GLuint program;
 };
+#endif
 
 } // namespace KWin