1 files changed, 133 insertions, 0 deletions
diff --git a/libs/hwui/renderstate/Stencil.cpp b/libs/hwui/renderstate/Stencil.cpp
new file mode 100644
index 0000000..cedb233
--- /dev/null
+++ b/libs/hwui/renderstate/Stencil.cpp
@@ -0,0 +1,133 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "renderstate/Stencil.h"
+
+#include "Caches.h"
+#include "Debug.h"
+#include "Extensions.h"
+#include "Properties.h"
+
+#include <GLES2/gl2ext.h>
+
+namespace android {
+namespace uirenderer {
+
+#if DEBUG_STENCIL
+#define STENCIL_WRITE_VALUE 0xff
+#define STENCIL_MASK_VALUE 0xff
+#else
+#define STENCIL_WRITE_VALUE 0x1
+#define STENCIL_MASK_VALUE 0x1
+#endif
+
+Stencil::Stencil()
+        : mState(kDisabled) {
+}
+
+uint8_t Stencil::getStencilSize() {
+    return STENCIL_BUFFER_SIZE;
+}
+
+GLenum Stencil::getSmallestStencilFormat() {
+#if !DEBUG_STENCIL
+    const Extensions& extensions = Caches::getInstance().extensions();
+    if (extensions.has1BitStencil()) {
+        return GL_STENCIL_INDEX1_OES;
+    } else if (extensions.has4BitStencil()) {
+        return GL_STENCIL_INDEX4_OES;
+    }
+#endif
+    return GL_STENCIL_INDEX8;
+}
+
+void Stencil::clear() {
+    glClearStencil(0);
+    glClear(GL_STENCIL_BUFFER_BIT);
+}
+
+void Stencil::enableTest(int incrementThreshold) {
+    if (mState != kTest) {
+        enable();
+        if (incrementThreshold > 0) {
+            glStencilFunc(GL_EQUAL, incrementThreshold, 0xff);
+        } else {
+            glStencilFunc(GL_EQUAL, STENCIL_WRITE_VALUE, STENCIL_MASK_VALUE);
+        }
+        // We only want to test, let's keep everything
+        glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
+        glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+        glStencilMask(0);
+        mState = kTest;
+    }
+}
+
+void Stencil::enableWrite(int incrementThreshold) {
+    if (mState != kWrite) {
+        enable();
+        if (incrementThreshold > 0) {
+            glStencilFunc(GL_ALWAYS, 1, 0xff);
+            // The test always passes so the first two values are meaningless
+            glStencilOp(GL_INCR, GL_INCR, GL_INCR);
+        } else {
+            glStencilFunc(GL_ALWAYS, STENCIL_WRITE_VALUE, STENCIL_MASK_VALUE);
+            // The test always passes so the first two values are meaningless
+            glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);
+        }
+        glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
+        glStencilMask(0xff);
+        mState = kWrite;
+    }
+}
+
+void Stencil::enableDebugTest(GLint value, bool greater) {
+    enable();
+    glStencilFunc(greater ? GL_LESS : GL_EQUAL, value, 0xffffffff);
+    // We only want to test, let's keep everything
+    glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
+    mState = kTest;
+}
+
+void Stencil::enableDebugWrite() {
+    if (mState != kWrite) {
+        enable();
+        glStencilFunc(GL_ALWAYS, 0x1, 0xffffffff);
+        // The test always passes so the first two values are meaningless
+        glStencilOp(GL_KEEP, GL_KEEP, GL_INCR);
+        glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+        mState = kWrite;
+    }
+}
+
+void Stencil::enable() {
+    if (mState == kDisabled) {
+        glEnable(GL_STENCIL_TEST);
+    }
+}
+
+void Stencil::disable() {
+    if (mState != kDisabled) {
+        glDisable(GL_STENCIL_TEST);
+        mState = kDisabled;
+    }
+}
+
+void Stencil::dump() {
+    ALOGD("Stencil: state %d", mState);
+}
+
+}; // namespace uirenderer
+}; // namespace android