Restore ETC1 compressed texture support.

Brings back GL ETC1 support and adds Vulkan support as well.

Bug: skia:8684
Change-Id: Ie65da0a3172793081f0e4072f161bfb9b14678bc
Reviewed-on: https://skia-review.googlesource.com/c/179724
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>

1 files changed, 127 insertions, 0 deletions

diff --git a/gm/etc1.cpp b/gm/etc1.cpp
new file mode 100644
index 0000000000..8f11ee8793
--- /dev/null
+++ b/gm/etc1.cpp
@@ -0,0 +1,127 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "gm.h"
+#include "sk_tool_utils.h"
+#include "SkRandom.h"
+
+#if SK_SUPPORT_GPU
+#include "etc1.h"
+
+#include "GrContext.h"
+#include "GrGpu.h"
+#include "GrRenderTargetContext.h"
+#include "GrRenderTargetContextPriv.h"
+#include "GrTextureProxy.h"
+#include "effects/GrSimpleTextureEffect.h"
+#include "ops/GrFillRectOp.h"
+
+// Basic test of Ganesh's ETC1 support
+class ETC1GM : public skiagm::GM {
+public:
+    ETC1GM() {
+        this->setBGColor(0xFFCCCCCC);
+    }
+
+protected:
+    SkString onShortName() override {
+        return SkString("etc1");
+    }
+
+    SkISize onISize() override {
+        return SkISize::Make(kTexWidth + 2*kPad, kTexHeight + 2*kPad);
+    }
+
+    void onOnceBeforeDraw() override {
+        SkBitmap bm;
+        SkImageInfo ii = SkImageInfo::Make(kTexWidth, kTexHeight, kRGB_565_SkColorType,
+                                           kOpaque_SkAlphaType);
+        bm.allocPixels(ii);
+
+        bm.erase(SK_ColorBLUE, SkIRect::MakeWH(kTexWidth, kTexHeight));
+
+        for (int y = 0; y < kTexHeight; y += 4) {
+            for (int x = 0; x < kTexWidth; x += 4) {
+                bm.erase((x+y) % 8 ? SK_ColorRED : SK_ColorGREEN, SkIRect::MakeXYWH(x, y, 4, 4));
+            }
+        }
+
+        int size = etc1_get_encoded_data_size(bm.width(), bm.height());
+        fETC1Data.reset(size);
+
+        unsigned char* pixels = (unsigned char*) fETC1Data.get();
+
+        if (etc1_encode_image((unsigned char*) bm.getAddr16(0, 0),
+                              bm.width(), bm.height(), 2, bm.rowBytes(), pixels)) {
+            fETC1Data.reset();
+        }
+    }
+
+    void onDraw(SkCanvas* canvas) override {
+        GrRenderTargetContext* renderTargetContext =
+            canvas->internal_private_accessTopLayerRenderTargetContext();
+        if (!renderTargetContext) {
+            skiagm::GM::DrawGpuOnlyMessage(canvas);
+            return;
+        }
+
+        GrContext* context = canvas->getGrContext();
+        if (!context) {
+            return;
+        }
+
+        GrBackendTexture tex = context->contextPriv().getGpu()->createTestingOnlyBackendTexture(
+            fETC1Data.get(),
+            kTexWidth,
+            kTexHeight,
+            GrColorType::kRGB_ETC1,
+            false,
+            GrMipMapped::kNo,
+            kTexWidth/2); // rowbytes are meaningless for compressed textures, but this is
+                          // basically right
+
+        if (!tex.isValid()) {
+            return;
+        }
+
+        auto proxy = context->contextPriv().proxyProvider()->wrapBackendTexture(
+                                                                 tex, kTopLeft_GrSurfaceOrigin,
+                                                                 kAdopt_GrWrapOwnership,
+                                                                 kRead_GrIOType);
+        if (!proxy) {
+            return;
+        }
+
+        const SkMatrix trans = SkMatrix::MakeTrans(-kPad, -kPad);
+
+        auto fp = GrSimpleTextureEffect::Make(proxy, trans);
+
+        GrPaint grPaint;
+        grPaint.setXPFactory(GrPorterDuffXPFactory::Get(SkBlendMode::kSrc));
+        grPaint.addColorFragmentProcessor(std::move(fp));
+
+        SkRect rect = SkRect::MakeXYWH(kPad, kPad, kTexWidth, kTexHeight);
+
+        renderTargetContext->priv().testingOnly_addDrawOp(
+            GrFillRectOp::Make(context, std::move(grPaint), GrAAType::kNone, SkMatrix::I(), rect));
+    }
+
+private:
+    static const int kPad = 8;
+    static const int kTexWidth = 16;
+    static const int kTexHeight = 20;
+
+    SkAutoTMalloc<char> fETC1Data;
+
+    typedef GM INHERITED;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+
+DEF_GM(return new ETC1GM;)
+
+#endif