Remove OFFSCREEN_FRAMEBUFFER_FORBID_VAO_PATH. NFC (emscripten-core#23056)

This was the only remaining test-only setting. The same effect can be
achieved instead using some EM_ASM.

Author: sbc100

src/library_webgl.js

@@ -940,7 +940,6 @@ for (/**@suppress{duplicate}*/var i = 0; i <= {{{ GL_POOL_TEMP_BUFFERS_SIZE }}};
       gl.uniform1i(gl.getUniformLocation(blitProgram, "sampler"), 0);
       gl.useProgram(null);
 
-      context.defaultVao = undefined;
       if (gl.createVertexArray) {
         context.defaultVao = gl.createVertexArray();
         gl.bindVertexArray(context.defaultVao);
@@ -1020,17 +1019,13 @@ for (/**@suppress{duplicate}*/var i = 0; i <= {{{ GL_POOL_TEMP_BUFFERS_SIZE }}};
           gl.drawArrays(5/*GL_TRIANGLE_STRIP*/, 0, 4);
         }
 
-#if !OFFSCREEN_FRAMEBUFFER_FORBID_VAO_PATH
         if (context.defaultVao) {
           // WebGL 2 or OES_vertex_array_object
           var prevVAO = gl.getParameter(0x85B5 /*GL_VERTEX_ARRAY_BINDING*/);
           gl.bindVertexArray(context.defaultVao);
           draw();
           gl.bindVertexArray(prevVAO);
-        }
-        else
-#endif
-        {
+        } else {
           var prevVertexAttribPointer = {
             buffer: gl.getVertexAttrib(context.blitPosLoc, 0x889F /*GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING*/),
             size: gl.getVertexAttrib(context.blitPosLoc, 0x8623 /*GL_VERTEX_ATTRIB_ARRAY_SIZE*/),

src/settings.js

@@ -2186,14 +2186,6 @@ var LEGACY_RUNTIME = false;
 // [link]
 var SIGNATURE_CONVERSIONS = [];
 
-//===========================================
-// Internal, used for testing only, from here
-//===========================================
-
-// Internal (testing only): Disables the blitOffscreenFramebuffer VAO path.
-// [link]
-var OFFSCREEN_FRAMEBUFFER_FORBID_VAO_PATH = false;
-
 // For renamed settings the format is:
 // [OLD_NAME, NEW_NAME]
 // For removed settings (which now effectively have a fixed value and can no

test/browser/webgl_offscreen_framebuffer_swap_with_bad_state.c

@@ -27,6 +27,13 @@ int main() {
 
   EMSCRIPTEN_WEBGL_CONTEXT_HANDLE ctx = emscripten_webgl_create_context("#canvas", &attr);
   emscripten_webgl_make_context_current(ctx);
+#ifdef TEST_DISABLE_VAO
+  EM_ASM({
+    console.log(GL.currentContext.defaultVao);
+    assert(GL.currentContext.defaultVao);
+    GL.currentContext.defaultVao = undefined;
+  });
+#endif
 
 #if !TEST_WEBGL2 && TEST_VERIFY_WEBGL1_VAO_SUPPORT
   // This test cannot run without browser support for OES_vertex_array_object.

test/test_browser.py

@@ -4321,14 +4321,14 @@ def test_webgl_vao_without_automatic_extensions(self):
   @requires_graphics_hardware
   @parameterized({
     # full state restoration path on WebGL 1.0
-    'gl1_no_vao': (['-sMAX_WEBGL_VERSION=1', '-sOFFSCREEN_FRAMEBUFFER_FORBID_VAO_PATH'],),
+    'gl1_no_vao': (['-sMAX_WEBGL_VERSION=1', '-DTEST_DISABLE_VAO'],),
     # VAO path on WebGL 1.0
     'gl1': (['-sMAX_WEBGL_VERSION=1', '-DTEST_VERIFY_WEBGL1_VAO_SUPPORT=1'],),
     'gl1_max_gl2': (['-sMAX_WEBGL_VERSION=2'],),
     # VAO path on WebGL 2.0
     'gl2': (['-sMAX_WEBGL_VERSION=2', '-DTEST_WEBGL2=1', '-DTEST_ANTIALIAS=1'],),
     # full state restoration path on WebGL 2.0
-    'gl2_no_vao': (['-sMAX_WEBGL_VERSION=2', '-DTEST_WEBGL2=1', '-DTEST_ANTIALIAS=1', '-sOFFSCREEN_FRAMEBUFFER_FORBID_VAO_PATH'],),
+    'gl2_no_vao': (['-sMAX_WEBGL_VERSION=2', '-DTEST_WEBGL2=1', '-DTEST_ANTIALIAS=1', '-DTEST_DISABLE_VAO'],),
     # blitFramebuffer path on WebGL 2.0 (falls back to VAO on Firefox < 67)
     'gl2_no_aa': (['-sMAX_WEBGL_VERSION=2', '-DTEST_WEBGL2=1', '-DTEST_ANTIALIAS=0'],),
   })

tools/maint/update_settings_docs.py

@@ -80,7 +80,7 @@ def write_file(f):
   current_comment = []
   current_tags = []
   for line in read_file(path_from_root('src/settings.js')).splitlines():
-    if 'Internal, used for testing only, from here' in line:
+    if 'LEGACY_SETTINGS' in line:
       break
     if not line:
       current_comment = []