Initial version of external_oes texture support and unit test

Committed: https://skia.googlesource.com/skia/+/27a048700778d4cebfc23301d1780649791b0e03

Review URL: https://codereview.chromium.org/1451683002
diff --git a/tests/EGLImageTest.cpp b/tests/EGLImageTest.cpp
new file mode 100644
index 0000000..32e74f8
--- /dev/null
+++ b/tests/EGLImageTest.cpp
@@ -0,0 +1,169 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "Test.h"
+#if SK_SUPPORT_GPU
+#include "GrContext.h"
+#include "GrContextFactory.h"
+#include "gl/GrGLGpu.h"
+#include "gl/GrGLUtil.h"
+#include "gl/SkGLContext.h"
+
+static void cleanup(SkGLContext* glctx0, GrGLuint texID0, SkGLContext* glctx1, GrContext* grctx1,
+                    const GrGLTextureInfo* grbackendtex1, GrEGLImage image1) {
+    if (glctx1) {
+        glctx1->makeCurrent();
+        if (grctx1) {
+            if (grbackendtex1) {
+                GrGLGpu* gpu1 = static_cast<GrGLGpu*>(grctx1->getGpu());
+                GrBackendObject handle = reinterpret_cast<GrBackendObject>(grbackendtex1);
+                gpu1->deleteTestingOnlyBackendTexture(handle, false);
+            }
+            grctx1->unref();
+        }
+        if (GR_EGL_NO_IMAGE != image1) {
+            glctx1->destroyEGLImage(image1);
+        }
+        glctx1->unref();
+    }
+
+    glctx0->makeCurrent();
+    if (texID0) {
+        GR_GL_CALL(glctx0->gl(), DeleteTextures(1, &texID0));
+    }
+}
+
+DEF_GPUTEST(EGLImageTest, reporter, factory) {
+    for (int glCtxType = 0; glCtxType < GrContextFactory::kGLContextTypeCnt; ++glCtxType) {
+        GrContextFactory::GLContextType type = (GrContextFactory::GLContextType)glCtxType;
+        if (!GrContextFactory::IsRenderingGLContext(type)) {
+            continue;
+        }
+        
+        // Try to create a second GL context and then check if the contexts have necessary
+        // extensions to run this test.
+
+        GrContext* context0 = factory->get(type);
+        if (!context0) {
+            continue;
+        }
+        SkGLContext* glCtx0 = factory->getGLContext(type);
+        SkASSERT(glCtx0);
+        if (kGLES_GrGLStandard != glCtx0->gl()->fStandard) {
+            continue;
+        }
+        GrGLGpu* gpu0 = static_cast<GrGLGpu*>(context0->getGpu());
+        if (!gpu0->glCaps().externalTextureSupport()) {
+            continue;
+        }
+
+        SkGLContext* glCtx1 = glCtx0->createNew();
+        if (!glCtx1) {
+            continue;
+        }
+        GrContext* context1 = GrContext::Create(kOpenGL_GrBackend, (GrBackendContext)glCtx1->gl());
+        const GrGLTextureInfo* backendTexture1 = nullptr;
+        GrEGLImage image = GR_EGL_NO_IMAGE;
+        GrGLTextureInfo externalTexture;
+        externalTexture.fID = 0;
+
+        if (!context1) {
+            cleanup(glCtx0, externalTexture.fID, glCtx1, context1, backendTexture1, image);
+            continue;
+        }
+
+        if (!glCtx1->gl()->hasExtension("EGL_KHR_image") ||
+            !glCtx1->gl()->hasExtension("EGL_KHR_gl_texture_2D_image")) {
+            cleanup(glCtx0, externalTexture.fID, glCtx1, context1, backendTexture1, image);
+            continue;
+        }
+
+///////////////////////////////// CONTEXT 1 ///////////////////////////////////
+
+        // Use GL Context 1 to create a texture unknown to GrContext.
+        context1->flush();
+        GrGpu* gpu1 = context1->getGpu();
+        static const int kSize = 100;
+        backendTexture1 = reinterpret_cast<const GrGLTextureInfo*>(
+            gpu1->createTestingOnlyBackendTexture(nullptr, kSize, kSize, kRGBA_8888_GrPixelConfig));
+        if (!backendTexture1 || !backendTexture1->fID) {
+            ERRORF(reporter, "Error creating texture for EGL Image");
+            cleanup(glCtx0, externalTexture.fID, glCtx1, context1, backendTexture1, image);
+            continue;
+        }
+        if (GR_GL_TEXTURE_2D != backendTexture1->fTarget) {
+            ERRORF(reporter, "Expected backend texture to be 2D");
+            cleanup(glCtx0, externalTexture.fID, glCtx1, context1, backendTexture1, image);
+            continue;
+        }
+
+        // Wrap the texture in an EGLImage
+        image = glCtx1->texture2DToEGLImage(backendTexture1->fID);
+        if (GR_EGL_NO_IMAGE == image) {
+            ERRORF(reporter, "Error creating EGL Image from texture");
+            cleanup(glCtx0, externalTexture.fID, glCtx1, context1, backendTexture1, image);
+            continue;
+        }
+
+        // Populate the texture using GL context 1. Important to use TexSubImage as TexImage orphans
+        // the EGL image. Also, this must be done after creating the EGLImage as the texture
+        // contents may not be preserved when the image is created.
+        SkAutoTMalloc<uint32_t> pixels(kSize * kSize);
+        for (int i = 0; i < kSize*kSize; ++i) {
+            pixels.get()[i] = 0xDDAABBCC;
+        }
+        GR_GL_CALL(glCtx1->gl(), ActiveTexture(GR_GL_TEXTURE0));
+        GR_GL_CALL(glCtx1->gl(), BindTexture(backendTexture1->fTarget, backendTexture1->fID));
+        GR_GL_CALL(glCtx1->gl(), TexSubImage2D(backendTexture1->fTarget, 0, 0, 0, kSize, kSize,
+                                               GR_GL_RGBA, GR_GL_UNSIGNED_BYTE, pixels.get()));
+        GR_GL_CALL(glCtx1->gl(), Finish());
+        // We've been making direct GL calls in GL context 1, let GrContext 1 know its internal
+        // state is invalid.
+        context1->resetContext();        
+
+///////////////////////////////// CONTEXT 0 ///////////////////////////////////
+
+        // Make a new texture ID in GL Context 0 from the EGL Image
+        glCtx0->makeCurrent();
+        externalTexture.fTarget = GR_GL_TEXTURE_EXTERNAL;
+        externalTexture.fID = glCtx0->eglImageToExternalTexture(image);
+
+        // Wrap this texture ID in a GrTexture
+        GrBackendTextureDesc externalDesc;
+        externalDesc.fConfig = kRGBA_8888_GrPixelConfig;
+        externalDesc.fWidth = kSize;
+        externalDesc.fHeight = kSize;
+        externalDesc.fTextureHandle = reinterpret_cast<GrBackendObject>(&externalTexture);
+        SkAutoTUnref<GrTexture> externalTextureObj(
+            context0->textureProvider()->wrapBackendTexture(externalDesc));
+        if (!externalTextureObj) {
+            ERRORF(reporter, "Error wrapping external texture in GrTexture.");
+            cleanup(glCtx0, externalTexture.fID, glCtx1, context1, backendTexture1, image);
+            continue;
+        }
+
+        // Read the pixels and see if we get the values set in GL context 1
+        memset(pixels.get(), 0, sizeof(uint32_t)*kSize*kSize);
+        bool read = externalTextureObj->readPixels(0, 0, kSize, kSize, kRGBA_8888_GrPixelConfig,
+                                                   pixels.get());
+        if (!read) {
+            ERRORF(reporter, "Error reading external texture.");
+            cleanup(glCtx0, externalTexture.fID, glCtx1, context1, backendTexture1, image);
+            continue;
+        }
+        for (int i = 0; i < kSize*kSize; ++i) {
+            if (pixels.get()[i] != 0xDDAABBCC) {
+                ERRORF(reporter, "Error, external texture pixel value %d should be 0xDDAABBCC,"
+                                 " got 0x%08x.", pixels.get()[i]);
+                break;
+            }
+        }
+        cleanup(glCtx0, externalTexture.fID, glCtx1, context1, backendTexture1, image);
+    }
+}
+
+#endif