Merge pull request #77085 from BastiaanOlij/visualise_direction_shadowmap_frustum

Draw frustum splices ontop of direction shadow atlas for debug purposes

servers/rendering/renderer_rd/shaders/effects/shadow_frustum.glsl

@@ -0,0 +1,41 @@
+/* clang-format off */
+#[vertex]
+
+#version 450
+
+#VERSION_DEFINES
+
+/* clang-format on */
+
+layout(push_constant, std430) uniform Info {
+	mat4 mvp;
+	vec4 color;
+}
+info;
+
+layout(location = 0) in vec3 vertex_attrib;
+
+void main() {
+	vec4 vertex = info.mvp * vec4(vertex_attrib, 1.0);
+	vertex.xyz /= vertex.w;
+	gl_Position = vec4(vertex.xy, 0.0, 1.0);
+}
+
+/* clang-format off */
+#[fragment]
+
+#version 450
+
+#VERSION_DEFINES
+
+layout(push_constant, std430) uniform Info {
+	mat4 mvp;
+	vec4 color;
+}
+info;
+
+layout(location = 0) out vec4 frag_color;
+
+void main() {
+	frag_color = info.color;
+}