From 29c3f352797d9d2ddf055d8f888e7694ef8b3947 Mon Sep 17 00:00:00 2001 From: Jesse Hall Date: Tue, 21 May 2013 15:36:55 -0700 Subject: [PATCH] Prevent opaque windows from making framebuffer translucent To keep the code readable now that we have four different texenv configurations, this change separates the decisions about what configuration to use from the GL calls to set up the configuration. Bug: 8963244 Change-Id: Ia07a306a7809ba8f93493d0160ccbd509e948581 --- services/surfaceflinger/Layer.cpp | 95 +++++++++++++++++----- services/surfaceflinger/SurfaceFlinger.cpp | 18 ++++ services/surfaceflinger/SurfaceFlinger.h | 13 +++ 3 files changed, 107 insertions(+), 19 deletions(-) diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp index c15dfd538..ee692227e 100644 --- a/services/surfaceflinger/Layer.cpp +++ b/services/surfaceflinger/Layer.cpp @@ -559,31 +559,88 @@ void Layer::clearWithOpenGL( clearWithOpenGL(hw, clip, 0,0,0,0); } +static void setupOpenGL10(bool premultipliedAlpha, bool opaque, int alpha) { + // OpenGL ES 1.0 doesn't support texture combiners. + // This path doesn't properly handle opaque layers that have non-opaque + // alpha values. The alpha channel will be copied into the framebuffer or + // screenshot, so if the framebuffer or screenshot is blended on top of + // something else, whatever is below the window will incorrectly show + // through. + if (CC_UNLIKELY(alpha < 0xFF)) { + GLfloat floatAlpha = alpha * (1.0f / 255.0f); + if (premultipliedAlpha) { + glColor4f(floatAlpha, floatAlpha, floatAlpha, floatAlpha); + } else { + glColor4f(1.0f, 1.0f, 1.0f, floatAlpha); + } + glTexEnvx(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); + } else { + glTexEnvx(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); + } +} + +static void setupOpenGL11(bool premultipliedAlpha, bool opaque, int alpha) { + GLenum combineRGB; + GLenum combineAlpha; + GLenum src0Alpha; + GLfloat envColor[4]; + + if (CC_UNLIKELY(alpha < 0xFF)) { + // Cv = premultiplied ? Cs*alpha : Cs + // Av = !opaque ? alpha*As : 1.0 + combineRGB = premultipliedAlpha ? GL_MODULATE : GL_REPLACE; + combineAlpha = !opaque ? GL_MODULATE : GL_REPLACE; + src0Alpha = GL_CONSTANT; + envColor[0] = alpha * (1.0f / 255.0f); + } else { + // Cv = Cs + // Av = opaque ? 1.0 : As + combineRGB = GL_REPLACE; + combineAlpha = GL_REPLACE; + src0Alpha = opaque ? GL_CONSTANT : GL_TEXTURE; + envColor[0] = 1.0f; + } + + glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE); + glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB, combineRGB); + glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_RGB, GL_TEXTURE); + glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB, GL_SRC_COLOR); + if (combineRGB == GL_MODULATE) { + glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_RGB, GL_CONSTANT); + glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB, GL_SRC_COLOR); + } + glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ALPHA, combineAlpha); + glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ALPHA, src0Alpha); + glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA, GL_SRC_ALPHA); + if (combineAlpha == GL_MODULATE) { + glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_ALPHA, GL_TEXTURE); + glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_ALPHA, GL_SRC_ALPHA); + } + if (combineRGB == GL_MODULATE || src0Alpha == GL_CONSTANT) { + envColor[1] = envColor[0]; + envColor[2] = envColor[0]; + envColor[3] = envColor[0]; + glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, envColor); + } +} + void Layer::drawWithOpenGL( const sp& hw, const Region& clip) const { const uint32_t fbHeight = hw->getHeight(); const State& s(drawingState()); - GLenum src = mPremultipliedAlpha ? GL_ONE : GL_SRC_ALPHA; - if (CC_UNLIKELY(s.alpha < 0xFF)) { - const GLfloat alpha = s.alpha * (1.0f/255.0f); - if (mPremultipliedAlpha) { - glColor4f(alpha, alpha, alpha, alpha); - } else { - glColor4f(1, 1, 1, alpha); - } - glEnable(GL_BLEND); - glBlendFunc(src, GL_ONE_MINUS_SRC_ALPHA); - glTexEnvx(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); + if (mFlinger->getGlesVersion() == GLES_VERSION_1_0) { + setupOpenGL10(mPremultipliedAlpha, isOpaque(), s.alpha); } else { - glColor4f(1, 1, 1, 1); - glTexEnvx(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); - if (!isOpaque()) { - glEnable(GL_BLEND); - glBlendFunc(src, GL_ONE_MINUS_SRC_ALPHA); - } else { - glDisable(GL_BLEND); - } + setupOpenGL11(mPremultipliedAlpha, isOpaque(), s.alpha); + } + + if (s.alpha < 0xFF || !isOpaque()) { + glEnable(GL_BLEND); + glBlendFunc(mPremultipliedAlpha ? GL_ONE : GL_SRC_ALPHA, + GL_ONE_MINUS_SRC_ALPHA); + } else { + glDisable(GL_BLEND); } LayerMesh mesh; diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp index 6ab33ef31..fbd9f2552 100644 --- a/services/surfaceflinger/SurfaceFlinger.cpp +++ b/services/surfaceflinger/SurfaceFlinger.cpp @@ -414,6 +414,22 @@ EGLContext SurfaceFlinger::createGLContext(EGLDisplay display, EGLConfig config) return ctxt; } +static GlesVersion parseGlesVersion(const char* str) { + int major, minor; + if (sscanf(str, "OpenGL ES-CM %d.%d", &major, &minor) != 2) { + ALOGW("Unable to parse GL_VERSION string: \"%s\"", str); + return GLES_VERSION_1_0; + } + + if (major == 1 && minor == 0) return GLES_VERSION_1_0; + if (major == 1 && minor >= 1) return GLES_VERSION_1_1; + if (major == 2 && minor >= 0) return GLES_VERSION_2_0; + if (major == 3 && minor >= 0) return GLES_VERSION_3_0; + + ALOGW("Unrecognized OpenGL ES version: %d.%d", major, minor); + return GLES_VERSION_1_0; +} + void SurfaceFlinger::initializeGL(EGLDisplay display) { GLExtensions& extensions(GLExtensions::getInstance()); extensions.initWithGLStrings( @@ -425,6 +441,8 @@ void SurfaceFlinger::initializeGL(EGLDisplay display) { eglQueryString(display, EGL_VERSION), eglQueryString(display, EGL_EXTENSIONS)); + mGlesVersion = parseGlesVersion(extensions.getVersion()); + glGetIntegerv(GL_MAX_TEXTURE_SIZE, &mMaxTextureSize); glGetIntegerv(GL_MAX_VIEWPORT_DIMS, mMaxViewportDims); diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h index e7745b8ca..089c2659d 100644 --- a/services/surfaceflinger/SurfaceFlinger.h +++ b/services/surfaceflinger/SurfaceFlinger.h @@ -72,6 +72,13 @@ enum { eTransactionMask = 0x07 }; +enum GlesVersion { + GLES_VERSION_1_0 = 0x10000, + GLES_VERSION_1_1 = 0x10001, + GLES_VERSION_2_0 = 0x20000, + GLES_VERSION_3_0 = 0x30000, +}; + class SurfaceFlinger : public BinderService, public BnSurfaceComposer, private IBinder::DeathRecipient, @@ -121,6 +128,11 @@ public: // TODO: this should be made accessible only to HWComposer const Vector< sp >& getLayerSortedByZForHwcDisplay(int id); + // return the version of the OpenGL ES composition context + GlesVersion getGlesVersion() const { + return mGlesVersion; + } + private: friend class Client; friend class DisplayEventConnection; @@ -421,6 +433,7 @@ private: EGLConfig mEGLConfig; EGLDisplay mEGLDisplay; EGLint mEGLNativeVisualId; + GlesVersion mGlesVersion; sp mBuiltinDisplays[DisplayDevice::NUM_DISPLAY_TYPES]; // Can only accessed from the main thread, these members