Rewrite Radiance and Reflection probes to use Octahedral maps.

Co-authored-by: clayjohn <claynjohn@gmail.com>

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

@@ -0,0 +1,36 @@
+#[vertex]
+
+#version 450
+
+#VERSION_DEFINES
+
+layout(location = 0) out vec2 uv_interp;
+
+void main() {
+	vec2 base_arr[3] = vec2[](vec2(-1.0, -3.0), vec2(-1.0, 1.0), vec2(3.0, 1.0));
+	uv_interp = base_arr[gl_VertexIndex];
+	gl_Position = vec4(uv_interp, 0.0, 1.0);
+}
+
+#[fragment]
+
+#version 450
+
+#VERSION_DEFINES
+
+#include "../oct_inc.glsl"
+
+layout(location = 0) in vec2 uv_interp;
+layout(location = 0) out vec4 frag_color;
+
+layout(set = 0, binding = 0) uniform samplerCube source_cube;
+
+layout(push_constant, std430) uniform Params {
+	float border_size;
+}
+params;
+
+void main() {
+	vec3 dir = oct_to_vec3_with_border(uv_interp * 0.5 + 0.5, params.border_size);
+	frag_color = vec4(texture(source_cube, dir).rgb, 1.0);
+}