Texturing support for RECTANGLE textures.

gm/rectangletexture.cpp

Index: gm/rectangletexture.cpp
diff --git a/gm/rectangletexture.cpp b/gm/rectangletexture.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..0889063a1f1d9916f340f00faf997d3e58089002
--- /dev/null
+++ b/gm/rectangletexture.cpp
@@ -0,0 +1,191 @@
+
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+// This test only works with the GPU backend.
+
+#include "gm.h"
+
+#if SK_SUPPORT_GPU
+
+#include "GrContext.h"
+#include "GrTest.h"
+#include "SkBitmap.h"
+#include "SkGradientShader.h"
+#include "SkImage.h"
+
+namespace skiagm {
+class RectangleTexture : public GM {
+public:
+    RectangleTexture() {
+        this->setBGColor(0xFFFFFFFF);
+    }
+
+protected:
+    SkString onShortName() override {
+        return SkString("rectangle_texture");
+    }
+
+    SkISize onISize() override {
+        return SkISize::Make(1035, 240);
+    }
+
+    void fillPixels(int width, int height, void *pixels) {
+        SkBitmap bmp;
+        bmp.setInfo(SkImageInfo::MakeN32(width, height, kOpaque_SkAlphaType), width * 4);
+        bmp.setPixels(pixels);
+        SkPaint paint;
+        SkCanvas canvas(bmp);
+        SkPoint pts[] = { {0, 0}, {0, SkIntToScalar(height)} };
+        SkColor colors0[] = { 0xFF1060B0 , 0xFF102030 };
+        paint.setShader(SkGradientShader::CreateLinear(pts, colors0, nullptr, 2,
+                                                       SkShader::kClamp_TileMode))->unref();
+        canvas.drawPaint(paint);
+
+        SkColor colors1[] = { 0xFFA07010 , 0xFFA02080 };
+        paint.setAntiAlias(true);
+        paint.setShader(SkGradientShader::CreateLinear(pts, colors1, nullptr, 2,
+                                                       SkShader::kClamp_TileMode))->unref();
+        canvas.drawCircle(SkIntToScalar(width) / 2, SkIntToScalar(height) / 2,
+                          SkIntToScalar(width + height) / 5, paint);
+    }
+
+    SkImage* createRectangleTextureImg(GrContext* context, int width, int height, void* pixels) {
+        if (!context) {
+            return nullptr;
+        }
+        GrGpu* gpu = context->getGpu();
+        if (!gpu) {
+            return nullptr;
+        }
+        const GrGLContext* glCtx = gpu->glContextForTesting();
+        if (!glCtx) {
+            return nullptr;
+        }
+
+        if (!(kGL_GrGLStandard == glCtx->standard() && glCtx->version() >= GR_GL_VER(3, 1)) &&
+            !glCtx->hasExtension("GL_ARB_texture_rectangle")) {
+            return nullptr;
+        }
+
+        // We will always create the GL texture as GL_RGBA, however the pixels uploaded may be
+        // be RGBA or BGRA, depending on how SkPMColor was compiled.
+        GrGLenum format;
+        if (kSkia8888_GrPixelConfig == kBGRA_8888_GrPixelConfig) {
+            format = GR_GL_BGRA;
+        } else {
+            SkASSERT(kSkia8888_GrPixelConfig == kRGBA_8888_GrPixelConfig);
+            format = GR_GL_RGBA;
+        }
+
+        const GrGLInterface* gl = glCtx->interface();
+// Useful for debugging whether errors result from use of RECTANGLE
+// #define TARGET GR_GL_TEXTURE_2D
+#define TARGET GR_GL_TEXTURE_RECTANGLE
+        GrGLuint id;
+        GR_GL_CALL(gl, GenTextures(1, &id));
+        GR_GL_CALL(gl, BindTexture(TARGET, id));
+        GR_GL_CALL(gl, TexParameteri(TARGET, GR_GL_TEXTURE_MAG_FILTER,
+                                     GR_GL_NEAREST));
+        GR_GL_CALL(gl, TexParameteri(TARGET, GR_GL_TEXTURE_MIN_FILTER,
+                                     GR_GL_NEAREST));
+        GR_GL_CALL(gl, TexParameteri(TARGET, GR_GL_TEXTURE_WRAP_S,
+                                     GR_GL_CLAMP_TO_EDGE));    
+        GR_GL_CALL(gl, TexParameteri(TARGET, GR_GL_TEXTURE_WRAP_T,
+                                     GR_GL_CLAMP_TO_EDGE));
+        GR_GL_CALL(gl, TexImage2D(TARGET, 0, GR_GL_RGBA, width, height, 0,
+                                  format, GR_GL_UNSIGNED_BYTE, pixels));
+
+
+        context->resetContext();
+        GrGLTextureInfo info;
+        info.fID = id;
+        info.fTarget = TARGET;
+        GrBackendTextureDesc desc;
+        desc.fConfig = kRGBA_8888_GrPixelConfig;
+        desc.fWidth = width;
+        desc.fHeight = height;
+        desc.fOrigin = kTopLeft_GrSurfaceOrigin;
+        desc.fTextureHandle = reinterpret_cast<GrBackendObject>(&info);
+        if (SkImage* image = SkImage::NewFromAdoptedTexture(context, desc)) {
+            return image;
+        }
+        GR_GL_CALL(gl, DeleteTextures(1, &id));
+        return nullptr;
+    }
+
+    void onDraw(SkCanvas* canvas) override {
+        GrRenderTarget* rt = canvas->internal_private_accessTopLayerRenderTarget();
+        GrContext* context;
+        if (!rt || !(context = rt->getContext())) {
+            skiagm::GM::DrawGpuOnlyMessage(canvas);
+            return;
+        }
+
+        static const int kWidth = 50;
+        static const int kHeight = 50;
+        static const SkScalar kPad = 5.f;
+
+        SkPMColor pixels[kWidth * kHeight];
+        this->fillPixels(kWidth, kHeight, pixels);
+        SkAutoTUnref<SkImage> rectImg(this->createRectangleTextureImg(context, kWidth, kHeight,
+                                                                      pixels));
+
+        if (!rectImg) {
+            SkPaint paint;
+            paint.setAntiAlias(true);
+            static const char* kMsg = "Could not create rectangle texture image.";
+            canvas->drawText(kMsg, strlen(kMsg), 10, 100, paint);
+            return;
+        }
+
+        static const SkFilterQuality kQualities[] = {
+            kNone_SkFilterQuality,
+            kLow_SkFilterQuality,
+            kMedium_SkFilterQuality,
+            kHigh_SkFilterQuality,
+        };
+
+        static const SkScalar kScales[] = { 1.0f, 1.2f, 0.75f };
+
+        canvas->translate(kPad, kPad);
+        for (auto s : kScales) {
+            canvas->save();
+            canvas->scale(s, s);
+            for (auto q : kQualities) {
+                    SkPaint plainPaint;
+                    plainPaint.setFilterQuality(q);
+                    canvas->drawImage(rectImg, 0, 0, &plainPaint);
+                    canvas->translate(kWidth + kPad, 0);
+
+                    SkPaint clampPaint;
+                    clampPaint.setFilterQuality(q);
+                    clampPaint.setShader(rectImg->newShader(SkShader::kClamp_TileMode,
+                                                            SkShader::kClamp_TileMode))->unref();
+                    canvas->drawRect(SkRect::MakeWH(1.5f * kWidth, 1.5f * kHeight), clampPaint);
+                    canvas->translate(kWidth * 1.5f + kPad, 0);
+
+                    SkPaint repeatPaint;
+                    repeatPaint.setFilterQuality(q);
+                    repeatPaint.setShader(rectImg->newShader(SkShader::kRepeat_TileMode,
+                                                             SkShader::kMirror_TileMode))->unref();
+                    canvas->drawRect(SkRect::MakeWH(1.5f * kWidth, 1.5f * kHeight), repeatPaint);
+                    canvas->translate(1.5f * kWidth + kPad, 0);
+            }
+            canvas->restore();
+            canvas->translate(0, kPad + 1.5f * kHeight * s);
+        }
+    }
+
+private:
+    typedef GM INHERITED;
+};
+
+DEF_GM(return new RectangleTexture;)
+}
+
+#endif