add GM to compare atlas and vertices
Bug: skia:6571
Change-Id: Ic97101c4623c7557eb33f69796232ed51a89af7e
Reviewed-on: https://skia-review.googlesource.com/14621
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Mike Reed <reed@google.com>
diff --git a/gm/drawatlas.cpp b/gm/drawatlas.cpp
index 2526177..d0609b5 100644
--- a/gm/drawatlas.cpp
+++ b/gm/drawatlas.cpp
@@ -169,4 +169,65 @@
canvas->drawPath(path, paint);
}
+#include "Resources.h"
+#include "SkColorFilter.h"
+#include "SkVertices.h"
+static sk_sp<SkVertices> make_vertices(sk_sp<SkImage> image, const SkRect& r,
+ SkColor color) {
+ SkPoint pos[4];
+ r.toQuad(pos);
+ SkColor colors[4] = { color, color, color, color };
+ return SkVertices::MakeCopy(SkVertices::kTriangleFan_VertexMode, 4,
+ pos, pos, colors);
+}
+
+/*
+ * drawAtlas and drawVertices have several things in common:
+ * - can create compound "shaders", combining texture and colors
+ * - these are combined via an explicit blendmode
+ * - like drawImage, they only respect parts of the paint
+ * - colorfilter, imagefilter, blendmode, alpha
+ *
+ * This GM produces a series of pairs of images (atlas | vertices).
+ * Each pair should look the same, and each set shows a different combination
+ * of alpha | colorFilter | mode
+ */
+DEF_SIMPLE_GM(compare_atlas_vertices, canvas, 560, 585) {
+ const SkRect tex = SkRect::MakeWH(128, 128);
+ const SkRSXform xform = SkRSXform::Make(1, 0, 0, 0);
+ const SkColor color = 0x884488CC;
+
+ auto image = GetResourceAsImage("mandrill_128.png");
+ auto verts = make_vertices(image, tex, color);
+ const sk_sp<SkColorFilter> filters[] = {
+ nullptr,
+ SkColorFilter::MakeModeFilter(0xFF00FF88, SkBlendMode::kModulate),
+ };
+ const SkBlendMode modes[] = {
+ SkBlendMode::kSrcOver,
+ SkBlendMode::kPlus,
+ };
+
+ canvas->translate(10, 10);
+ SkPaint paint;
+ for (SkBlendMode mode : modes) {
+ for (int alpha : { 0xFF, 0x7F }) {
+ paint.setAlpha(alpha);
+ canvas->save();
+ for (auto cf : filters) {
+ paint.setColorFilter(cf);
+ canvas->drawAtlas(image, &xform, &tex, &color, 1,
+ mode, &tex, &paint);
+ canvas->translate(128, 0);
+ paint.setShader(image->makeShader(SkShader::kClamp_TileMode,
+ SkShader::kClamp_TileMode));
+ canvas->drawVertices(verts, mode, paint);
+ paint.setShader(nullptr);
+ canvas->translate(145, 0);
+ }
+ canvas->restore();
+ canvas->translate(0, 145);
+ }
+ }
+}
