test: Shift the triangle apex to demonstrate the rendering comparison

.github/workflows/reusable-check-rendering.yml

@@ -71,19 +71,25 @@ jobs:
             pull_request) base=$(gh api "repos/$GITHUB_REPOSITORY/compare/$PR_BASE...$PR_HEAD_OWNER:$PR_HEAD" --jq .merge_base_commit.sha) || base="" ;;
             *) base=$(gh api "repos/$GITHUB_REPOSITORY/compare/main...$GITHUB_SHA" --jq .merge_base_commit.sha) || base="" ;;
           esac
-          runs=""
+          # A commit has no package when it was pushed together with later commits, or when its run
+          # skipped this game's build because nothing it builds from changed. The nearest ancestor
+          # with a package then renders the same.
+          commits=""
           if [ -n "$base" ]; then
-            runs=$(gh api "repos/$GITHUB_REPOSITORY/actions/runs?head_sha=$base" \
-              --jq ".workflow_runs[] | select(.id != $GITHUB_RUN_ID) | .id") || runs=""
+            commits=$(gh api "repos/$GITHUB_REPOSITORY/commits?sha=$base&per_page=20" --jq '.[].sha') || commits=""
           fi
-          for run in $runs; do
-            if gh run download "$run" --repo "$GITHUB_REPOSITORY" --name "$GAME-win32-rendering-tests" \
-              --dir build/rendering-tests-base; then
-              echo "Using the rendering tests of run $run for base commit $base"
-              echo "sha=$base" >> "$GITHUB_OUTPUT"
-              exit 0
-            fi
-            rm -rf build/rendering-tests-base
+          for commit in $commits; do
+            runs=$(gh api "repos/$GITHUB_REPOSITORY/actions/runs?head_sha=$commit" \
+              --jq ".workflow_runs[] | select(.id != $GITHUB_RUN_ID) | .id") || runs=""
+            for run in $runs; do
+              if gh run download "$run" --repo "$GITHUB_REPOSITORY" --name "$GAME-win32-rendering-tests" \
+                --dir build/rendering-tests-base; then
+                echo "Using the rendering tests of run $run for commit $commit (base commit $base)"
+                echo "sha=$commit" >> "$GITHUB_OUTPUT"
+                exit 0
+              fi
+              rm -rf build/rendering-tests-base
+            done
           done
           echo "::notice title=Rendering::No rendering tests found for base commit ${base:-unknown}, so the images are not compared"
 

Tests/Rendering/README.md

@@ -72,7 +72,9 @@ come from the Ubuntu 24.04 package repositories; these can receive updates.
 
 There are no stored reference images. The job also downloads the rendering test
 package of the base commit from its earlier GenCI run: the previous `main` commit
-for a push, otherwise the merge base with `main`. It runs both executables under
+for a push, otherwise the merge base with `main`. If that commit has no package,
+because it was pushed together with later commits or its build was skipped, the
+nearest ancestor with one renders the same and is used. It runs both executables under
 the same Wine, Mesa and DXVK, so a difference in the images comes from the code.
 `compare.py` compares every BMP and writes a job summary table and a
 `<game>-rendering-report.html` artifact with the base, result and difference

Tests/Rendering/d3d8_probe.cpp

@@ -60,7 +60,7 @@ bool RunD3D8Probe(const char *output)
     Check(device->SetTextureStageState(0, D3DTSS_COLORARG1, D3DTA_DIFFUSE), "Color arg");
     struct Vertex { float x, y, z, rhw; DWORD color; };
     const Vertex vertices[] = {
-        {128, 32, 0.5f, 1, 0xffff0000},
+        {136, 32, 0.5f, 1, 0xffff0000},
         {224, 224, 0.5f, 1, 0xff00ff00},
         {32, 224, 0.5f, 1, 0xff0000ff}
     };