Remove obsolete GLES3 backend

Due to the port to Vulkan and complete redesign of the rendering backend,
the `drivers/gles3` code is no longer usable in this state and is not
planned to be ported to the new architecture.

The GLES2 backend is kept (while still disabled and non-working) as it
will eventually be ported to serve as the low-end renderer for Godot 4.0.

Some GLES3 features might be selectively ported to the updated GLES2
backend if there's a need for them, and extensions we can use for that.

So long, OpenGL driver bugs!

1 files changed, 0 insertions, 45 deletions

diff --git a/drivers/gles3/shaders/canvas_shadow.glsl b/drivers/gles3/shaders/canvas_shadow.glsl
deleted file mode 100644
index 4f706c5505..0000000000
--- a/drivers/gles3/shaders/canvas_shadow.glsl
+++ /dev/null
@@ -1,45 +0,0 @@
-/* clang-format off */
-[vertex]
-
-uniform highp mat4 projection_matrix;
-/* clang-format on */
-uniform highp mat4 light_matrix;
-uniform highp mat4 world_matrix;
-uniform highp float distance_norm;
-
-layout(location = 0) in highp vec3 vertex;
-
-out highp vec4 position_interp;
-
-void main() {
-
-	gl_Position = projection_matrix * (light_matrix * (world_matrix * vec4(vertex, 1.0)));
-	position_interp = gl_Position;
-}
-
-/* clang-format off */
-[fragment]
-
-in highp vec4 position_interp;
-/* clang-format on */
-
-#ifdef USE_RGBA_SHADOWS
-layout(location = 0) out lowp vec4 distance_buf;
-#else
-layout(location = 0) out highp float distance_buf;
-#endif
-
-void main() {
-
-	highp float depth = ((position_interp.z / position_interp.w) + 1.0) * 0.5 + 0.0; // bias
-
-#ifdef USE_RGBA_SHADOWS
-
-	highp vec4 comp = fract(depth * vec4(255.0 * 255.0 * 255.0, 255.0 * 255.0, 255.0, 1.0));
-	comp -= comp.xxyz * vec4(0.0, 1.0 / 255.0, 1.0 / 255.0, 1.0 / 255.0);
-	distance_buf = comp;
-#else
-
-	distance_buf = depth;
-#endif
-}