Rename GLES2 driver to OpenGL to prepare for the upgrade to GLES3

- Use lowercase driver names for the `--rendering-driver`
  command line argument.

SConstruct

@@ -15,7 +15,7 @@ from collections import OrderedDict
 # Local
 import methods
 import glsl_builders
-import gles_builders
+import opengl_builders
 from platform_methods import run_in_subprocess
 
 # Scan possible build platforms
@@ -708,20 +708,11 @@ if selected_platform in platform_list:
     }
     env.Append(BUILDERS=GLSL_BUILDERS)
 
-    if not env["platform"] == "server":  # FIXME: detect GLES3
+    if not env["platform"] == "server":
         env.Append(
             BUILDERS={
-                "GLES3_GLSL": env.Builder(
-                    action=run_in_subprocess(gles_builders.build_gles3_headers),
-                    suffix="glsl.gen.h",
-                    src_suffix=".glsl",
-                )
-            }
-        )
-        env.Append(
-            BUILDERS={
-                "GLES2_GLSL": env.Builder(
-                    action=run_in_subprocess(gles_builders.build_gles2_headers),
+                "OpenGL_GLSL": env.Builder(
+                    action=run_in_subprocess(opengl_builders.build_opengl_headers),
                     suffix="glsl.gen.h",
                     src_suffix=".glsl",
                 )

core/core_bind.cpp

@@ -603,8 +603,8 @@ void OS::_bind_methods() {
 	ADD_PROPERTY_DEFAULT("low_processor_usage_mode", false);
 	ADD_PROPERTY_DEFAULT("low_processor_usage_mode_sleep_usec", 6900);
 
-	BIND_ENUM_CONSTANT(VIDEO_DRIVER_GLES2);
 	BIND_ENUM_CONSTANT(VIDEO_DRIVER_VULKAN);
+	BIND_ENUM_CONSTANT(VIDEO_DRIVER_OPENGL);
 
 	BIND_ENUM_CONSTANT(DAY_SUNDAY);
 	BIND_ENUM_CONSTANT(DAY_MONDAY);

core/core_bind.h

@@ -119,8 +119,8 @@ class OS : public Object {
 
 public:
 	enum VideoDriver {
-		VIDEO_DRIVER_GLES2,
 		VIDEO_DRIVER_VULKAN,
+		VIDEO_DRIVER_OPENGL,
 	};
 
 	enum Weekday {

doc/classes/Environment.xml

@@ -128,10 +128,10 @@
 			The bleed scale of the HDR glow.
 		</member>
 		<member name="glow_hdr_threshold" type="float" setter="set_glow_hdr_bleed_threshold" getter="get_glow_hdr_bleed_threshold" default="1.0">
-			The lower threshold of the HDR glow. When using the GLES2 renderer (which doesn't support HDR), this needs to be below [code]1.0[/code] for glow to be visible. A value of [code]0.9[/code] works well in this case.
+			The lower threshold of the HDR glow. When using the OpenGL renderer (which doesn't support HDR), this needs to be below [code]1.0[/code] for glow to be visible. A value of [code]0.9[/code] works well in this case.
 		</member>
 		<member name="glow_intensity" type="float" setter="set_glow_intensity" getter="get_glow_intensity" default="0.8">
-			The overall brightness multiplier of the glow effect. When using the GLES2 renderer, this should be increased to 1.5 to compensate for the lack of HDR rendering.
+			The overall brightness multiplier of the glow effect. When using the OpenGL renderer, this should be increased to 1.5 to compensate for the lack of HDR rendering.
 		</member>
 		<member name="glow_levels/1" type="float" setter="set_glow_level" getter="get_glow_level" default="0.0">
 			The intensity of the 1st level of glow. This is the most "local" level (least blurry).
@@ -160,7 +160,7 @@
 			If [code]true[/code], glow levels will be normalized so that summed together their intensities equal [code]1.0[/code].
 		</member>
 		<member name="glow_strength" type="float" setter="set_glow_strength" getter="get_glow_strength" default="1.0">
-			The strength of the glow effect. This applies as the glow is blurred across the screen and increases the distance and intensity of the blur. When using the GLES2 renderer, this should be increased to 1.3 to compensate for the lack of HDR rendering.
+			The strength of the glow effect. This applies as the glow is blurred across the screen and increases the distance and intensity of the blur. When using the OpenGL renderer, this should be increased to 1.3 to compensate for the lack of HDR rendering.
 		</member>
 		<member name="reflected_light_source" type="int" setter="set_reflection_source" getter="get_reflection_source" enum="Environment.ReflectionSource" default="0">
 		</member>

doc/classes/NinePatchRect.xml

@@ -68,11 +68,11 @@
 		</constant>
 		<constant name="AXIS_STRETCH_MODE_TILE" value="1" enum="AxisStretchMode">
 			Repeats the center texture across the NinePatchRect. This won't cause any visible distortion. The texture must be seamless for this to work without displaying artifacts between edges.
-			[b]Note:[/b] Only supported when using the GLES3 renderer. When using the GLES2 renderer, this will behave like [constant AXIS_STRETCH_MODE_STRETCH].
+			[b]Note:[/b] Only supported when using the Vulkan renderer. When using the OpenGL renderer, this will behave like [constant AXIS_STRETCH_MODE_STRETCH].
 		</constant>
 		<constant name="AXIS_STRETCH_MODE_TILE_FIT" value="2" enum="AxisStretchMode">
 			Repeats the center texture across the NinePatchRect, but will also stretch the texture to make sure each tile is visible in full. This may cause the texture to be distorted, but less than [constant AXIS_STRETCH_MODE_STRETCH]. The texture must be seamless for this to work without displaying artifacts between edges.
-			[b]Note:[/b] Only supported when using the GLES3 renderer. When using the GLES2 renderer, this will behave like [constant AXIS_STRETCH_MODE_STRETCH].
+			[b]Note:[/b] Only supported when using the Vulkan renderer. When using the OpenGL renderer, this will behave like [constant AXIS_STRETCH_MODE_STRETCH].
 		</constant>
 	</constants>
 </class>

doc/classes/OS.xml

@@ -455,12 +455,12 @@
 		</member>
 	</members>
 	<constants>
-		<constant name="VIDEO_DRIVER_GLES2" value="0" enum="VideoDriver">
-			The GLES2 rendering backend. It uses OpenGL ES 2.0 on mobile devices, OpenGL 2.1 on desktop platforms and WebGL 1.0 on the web.
-		</constant>
-		<constant name="VIDEO_DRIVER_VULKAN" value="1" enum="VideoDriver">
+		<constant name="VIDEO_DRIVER_VULKAN" value="0" enum="VideoDriver">
 			The Vulkan rendering backend.
 		</constant>
+		<constant name="VIDEO_DRIVER_OPENGL" value="1" enum="VideoDriver">
+			The OpenGL rendering backend. It uses OpenGL ES 3.0 on mobile devices, OpenGL 3.3 on desktop platforms and WebGL 2.0 on the web.
+		</constant>
 		<constant name="DAY_SUNDAY" value="0" enum="Weekday">
 			Sunday.
 		</constant>

drivers/SCsub

@@ -25,8 +25,7 @@ SConscript("winmidi/SCsub")
 # Graphics drivers
 if env["vulkan"]:
     SConscript("vulkan/SCsub")
-    SConscript("gles2/SCsub")
-    SConscript("gles_common/SCsub")
+    SConscript("opengl/SCsub")
     SConscript("gl_context/SCsub")
 else:
     SConscript("dummy/SCsub")