Simple Blender Render: include scene name in job settings

Include the current scene name in a hidden setting of the Simple Blender
Render, and pass that as CLI argument to Blender.

This ensures that the correct scene is rendered when working directly on
shared storage (as that does not have a copy of the blend file per job).

The job setting `"scene"` is still optional. If it's missing or empty,
the `--scene <scene name>` CLI arg will simply not be passed to Blender.

CHANGELOG.md

@@ -12,6 +12,7 @@ bugs in actually-released versions.
 - Security updates of some deendencies:
   - [GO-2024-2937: Parsing a corrupt or malicious image with invalid color indices can cause a panic](https://pkg.go.dev/vuln/GO-2024-2937)
 - Web interface: list the job's worker tag in the job details.
+- Ensure the submitted scene is rendered in a multi-scene blend file.
 
 ## 3.5 - released 2024-04-16
 

internal/manager/job_compilers/job_compilers_test.go

@@ -139,6 +139,41 @@ func TestSimpleBlenderRenderHappy(t *testing.T) {
 	assert.Equal(t, expectDeps, tVideo.Dependencies)
 }
 
+func TestSimpleBlenderRenderWithScene(t *testing.T) {
+	c := mockedClock(t)
+
+	s, err := Load(c)
+	require.NoError(t, err)
+
+	// Compiling a job should be really fast.
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Millisecond)
+	defer cancel()
+
+	sj := exampleSubmittedJob()
+	sj.Settings.AdditionalProperties["scene"] = "Test Scene"
+	aj, err := s.Compile(ctx, sj)
+	require.NoError(t, err)
+	require.NotNil(t, aj)
+
+	t0 := aj.Tasks[0]
+	expectCliArgs := []interface{}{ // They are strings, but Goja doesn't know that and will produce an []interface{}.
+		"--scene", "Test Scene",
+		"--render-output", "/render/sprites/farm_output/promo/square_ellie/square_ellie.lighting_light_breakdown2/######",
+		"--render-format", "PNG",
+		"--render-frame", "1..3",
+	}
+	assert.Equal(t, "render-1-3", t0.Name)
+	assert.Equal(t, 1, len(t0.Commands))
+	assert.Equal(t, "blender-render", t0.Commands[0].Name)
+	assert.EqualValues(t, AuthoredCommandParameters{
+		"exe":        "{blender}",
+		"exeArgs":    "{blenderArgs}",
+		"blendfile":  "/render/sf/jobs/scene123.blend",
+		"args":       expectCliArgs,
+		"argsBefore": make([]interface{}, 0),
+	}, t0.Commands[0].Parameters)
+}
+
 func TestJobWithoutTag(t *testing.T) {
 	c := mockedClock(t)
 

internal/manager/job_compilers/scripts/simple_blender_render.js

@@ -32,6 +32,8 @@ const JOB_TYPE = {
           description: "File extension used when rendering images" },
         { key: "has_previews", type: "bool", required: false, eval: "C.scene.render.image_settings.use_preview", visible: "hidden",
           description: "Whether Blender will render preview images."},
+        { key: "scene", type: "string", required: true, eval: "C.scene.name", visible: "web",
+          description: "Name of the scene to render."},
     ]
 };
 
@@ -100,6 +102,12 @@ function authorRenderTasks(settings, renderDir, renderOutput) {
     print("authorRenderTasks(", renderDir, renderOutput, ")");
     let renderTasks = [];
     let chunks = frameChunker(settings.frames, settings.chunk_size);
+
+    let baseArgs = [];
+    if (settings.scene) {
+      baseArgs = baseArgs.concat(["--scene", settings.scene]);
+    }
+
     for (let chunk of chunks) {
         const task = author.Task(`render-${chunk}`, "blender");
         const command = author.Command("blender-render", {
@@ -107,11 +115,11 @@ function authorRenderTasks(settings, renderDir, renderOutput) {
             exeArgs: "{blenderArgs}",
             argsBefore: [],
             blendfile: settings.blendfile,
-            args: [
+            args: baseArgs.concat([
                 "--render-output", path.join(renderDir, path.basename(renderOutput)),
                 "--render-format", settings.format,
                 "--render-frame", chunk.replaceAll("-", ".."), // Convert to Blender frame range notation.
-            ]
+            ])
         });
         task.addCommand(command);
         renderTasks.push(task);