Limit the Viewer MSAA options to the context's max sample count.
Selecting an MSAA option that the context does not support can cause
issues, so prevent those options from being displayed.
This fix was suggested by jvanverth@ during his review of
https://skia-review.googlesource.com/c/skia/+/287976
Bug: skia:10134
Change-Id: If8c35786da83e6ace336328281d7005cc75cf301
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/288096
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
diff --git a/tools/viewer/Viewer.cpp b/tools/viewer/Viewer.cpp
index ee5dbaf..6d41aad 100644
--- a/tools/viewer/Viewer.cpp
+++ b/tools/viewer/Viewer.cpp
@@ -1696,12 +1696,27 @@
}
if (ctx) {
+ // Determine the context's max sample count for MSAA radio buttons.
int sampleCount = fWindow->sampleCount();
- ImGui::Text("MSAA: "); ImGui::SameLine();
- ImGui::RadioButton("1", &sampleCount, 1); ImGui::SameLine();
- ImGui::RadioButton("4", &sampleCount, 4); ImGui::SameLine();
- ImGui::RadioButton("8", &sampleCount, 8); ImGui::SameLine();
- ImGui::RadioButton("16", &sampleCount, 16);
+ int maxMSAA = (fBackendType != sk_app::Window::kRaster_BackendType) ?
+ ctx->maxSurfaceSampleCountForColorType(kRGBA_8888_SkColorType) :
+ 1;
+
+ // Only display the MSAA radio buttons when there are options above 1x MSAA.
+ if (maxMSAA >= 4) {
+ ImGui::Text("MSAA: ");
+
+ for (int curMSAA = 1; curMSAA <= maxMSAA; curMSAA *= 2) {
+ // 2x MSAA works, but doesn't offer much of a visual improvement, so we
+ // don't show it in the list.
+ if (curMSAA == 2) {
+ continue;
+ }
+ ImGui::SameLine();
+ ImGui::RadioButton(SkStringPrintf("%d", curMSAA).c_str(),
+ &sampleCount, curMSAA);
+ }
+ }
if (sampleCount != params.fMSAASampleCount) {
params.fMSAASampleCount = sampleCount;