Add gms that test limited hw tessellation segments
Adds variations of trickycubicstrokes and widebuttcaps that limit the
max number of hardware tessellation segments to 5. This exercises our
stroking logic for splitting curves and joins when they require more
segments than are supported by the hardware.
Bug: skia:10419
Change-Id: Ie52374b89e30bfa021b2de74e3cd32e02ab734d0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/317268
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/gm/trickycubicstrokes.cpp b/gm/trickycubicstrokes.cpp
index 1840c9b..af26c18 100644
--- a/gm/trickycubicstrokes.cpp
+++ b/gm/trickycubicstrokes.cpp
@@ -16,12 +16,19 @@
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/core/SkTypes.h"
+#include "include/gpu/GrContextOptions.h"
+#include "include/gpu/GrRecordingContext.h"
#include "src/core/SkGeometry.h"
+#include "src/gpu/GrDrawingManager.h"
+#include "src/gpu/GrRecordingContextPriv.h"
+#include "src/gpu/tessellate/GrTessellationPathRenderer.h"
static constexpr float kStrokeWidth = 30;
static constexpr int kCellSize = 200;
static constexpr int kNumCols = 5;
static constexpr int kNumRows = 4;
+static constexpr int kTestWidth = kNumCols * kCellSize;
+static constexpr int kTestHeight = kNumRows * kCellSize;
enum class CellFillMode {
kStretch,
@@ -35,6 +42,7 @@
float fScale = 1;
};
+// This is a compilation of cubics that have given strokers grief. Feel free to add more.
static const TrickyCubic kTrickyCubics[] = {
{{{122, 737}, {348, 553}, {403, 761}, {400, 760}}, 4, CellFillMode::kStretch},
{{{244, 520}, {244, 518}, {1141, 634}, {394, 688}}, 4, CellFillMode::kStretch},
@@ -87,46 +95,26 @@
kScale
};
-// This is a compilation of cubics that have given strokers grief. Feel free to add more.
-class TrickyCubicStrokesGM : public skiagm::GM {
-public:
- TrickyCubicStrokesGM() {}
+static void draw_test(SkCanvas* canvas, const SkColor strokeColor) {
+ SkPaint strokePaint;
+ strokePaint.setAntiAlias(true);
+ strokePaint.setStrokeWidth(kStrokeWidth);
+ strokePaint.setColor(strokeColor);
+ strokePaint.setStyle(SkPaint::kStroke_Style);
-protected:
+ canvas->clear(SK_ColorBLACK);
- SkString onShortName() override {
- return SkString("trickycubicstrokes");
- }
+ for (size_t i = 0; i < SK_ARRAY_COUNT(kTrickyCubics); ++i) {
+ auto [originalPts, numPts, fillMode, scale] = kTrickyCubics[i];
- SkISize onISize() override {
- return SkISize::Make(kNumCols * kCellSize, kNumRows * kCellSize);
- }
-
- void onOnceBeforeDraw() override {
- fStrokePaint.setAntiAlias(true);
- fStrokePaint.setStrokeWidth(kStrokeWidth);
- fStrokePaint.setColor(SK_ColorGREEN);
- fStrokePaint.setStyle(SkPaint::kStroke_Style);
- }
-
- void onDraw(SkCanvas* canvas) override {
- canvas->clear(SK_ColorBLACK);
-
- for (size_t i = 0; i < SK_ARRAY_COUNT(kTrickyCubics); ++i) {
- const auto& trickyCubic = kTrickyCubics[i];
- SkPoint p[7];
- memcpy(p, trickyCubic.fPoints, sizeof(SkPoint) * 4);
- for (int j = 0; j < 4; ++j) {
- p[j] *= trickyCubic.fScale;
- }
- this->drawStroke(canvas, p, trickyCubic.fNumPts, i, trickyCubic.fFillMode);
+ SkASSERT(numPts <= 4);
+ SkPoint p[4];
+ memcpy(p, originalPts, sizeof(SkPoint) * numPts);
+ for (int j = 0; j < numPts; ++j) {
+ p[j] *= scale;
}
- }
- void drawStroke(SkCanvas* canvas, const SkPoint p[], int numPts, int cellID,
- CellFillMode fillMode) {
- auto cellRect = SkRect::MakeXYWH((cellID % kNumCols) * kCellSize,
- (cellID / kNumCols) * kCellSize,
+ auto cellRect = SkRect::MakeXYWH((i % kNumCols) * kCellSize, (i / kNumCols) * kCellSize,
kCellSize, kCellSize);
SkRect strokeBounds;
@@ -151,7 +139,7 @@
SkAutoCanvasRestore acr(canvas, true);
canvas->concat(matrix);
- fStrokePaint.setStrokeWidth(kStrokeWidth / matrix.getMaxScale());
+ strokePaint.setStrokeWidth(kStrokeWidth / matrix.getMaxScale());
SkPath path = SkPath().moveTo(p[0]);
if (numPts == 4) {
path.cubicTo(p[1], p[2], p[3]);
@@ -159,12 +147,54 @@
SkASSERT(numPts == 3);
path.quadTo(p[1], p[2]);
}
- canvas->drawPath(path, fStrokePaint);
+ canvas->drawPath(path, strokePaint);
+ }
+}
+
+DEF_SIMPLE_GM(trickycubicstrokes, canvas, kTestWidth, kTestHeight) {
+ draw_test(canvas, SK_ColorGREEN);
+}
+
+class TrickyCubicStrokes_tess_segs_5 : public skiagm::GpuGM {
+ SkString onShortName() override {
+ return SkString("trickycubicstrokes_tess_segs_5");
}
-private:
- SkPaint fStrokePaint;
- using INHERITED = GM;
+ SkISize onISize() override {
+ return SkISize::Make(kTestWidth, kTestHeight);
+ }
+
+ void modifyGrContextOptions(GrContextOptions* options) override {
+ // Pick a very small, odd (and better yet, prime) number of segments.
+ //
+ // - Odd because it makes the tessellation strip asymmetric, which will be important to test
+ // for future plans that involve drawing in reverse order.
+ //
+ // - >=4 because the tessellator code will just assume we have enough to combine a miter
+ // join and line in a single patch. (Requires 4 segments. Spec required minimum is 64.)
+ options->fMaxTessellationSegmentsOverride = 5;
+ // Only allow the tessellation path renderer.
+ options->fGpuPathRenderers = (GpuPathRenderers)((int)options->fGpuPathRenderers &
+ (int)GpuPathRenderers::kTessellation);
+ }
+
+ DrawResult onDraw(GrRecordingContext* context, GrRenderTargetContext*, SkCanvas* canvas,
+ SkString* errorMsg) override {
+ if (!context->priv().caps()->shaderCaps()->tessellationSupport() ||
+ !GrTessellationPathRenderer::IsSupported(*context->priv().caps())) {
+ errorMsg->set("Tessellation not supported.");
+ return DrawResult::kSkip;
+ }
+ auto opts = context->priv().drawingManager()->testingOnly_getOptionsForPathRendererChain();
+ if (!(opts.fGpuPathRenderers & GpuPathRenderers::kTessellation)) {
+ errorMsg->set("GrTessellationPathRenderer disabled.");
+ return DrawResult::kSkip;
+ }
+ // Suppress a tessellator warning message that caps.maxTessellationSegments is too small.
+ GrRecordingContextPriv::AutoSuppressWarningMessages aswm(context);
+ draw_test(canvas, SK_ColorRED);
+ return DrawResult::kOk;
+ }
};
-DEF_GM( return new TrickyCubicStrokesGM; )
+DEF_GM( return new TrickyCubicStrokes_tess_segs_5; )