1 files changed, 63 insertions, 0 deletions
diff --git a/client/map/tiles/portal.gdshader b/client/map/tiles/portal.gdshader
new file mode 100644
index 00000000..3ffd7d07
--- /dev/null
+++ b/client/map/tiles/portal.gdshader
@@ -0,0 +1,63 @@
+/*
+    Hurry Curry! - a game about cooking
+    Copyright 2024 metamuffin
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, version 3 of the License only.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+*/
+shader_type spatial;
+render_mode unshaded;
+
+uniform sampler2D screen_texture : hint_screen_texture, repeat_disable, filter_nearest;
+
+varying vec3 world_camera;
+varying vec3 world_position;
+varying mat4 untr;
+
+uniform float type : hint_range(-1.0, 1.0);
+uniform float size : hint_range(0.0, 2.0);
+
+void vertex() {
+	MODELVIEW_MATRIX = VIEW_MATRIX * mat4(
+		INV_VIEW_MATRIX[0],
+		INV_VIEW_MATRIX[1],
+		INV_VIEW_MATRIX[2],
+		MODEL_MATRIX[3]
+	);
+	world_position = VERTEX;
+	world_camera = (inverse(MODELVIEW_MATRIX) * vec4(0, 0, 0, 1)).xyz;
+	untr = MODELVIEW_MATRIX;
+}
+
+void fragment() {
+	vec3 ray = world_camera / size;
+	vec3 rv = normalize(world_position - world_camera);
+	vec3 em = vec3(0.);
+	bool hit = false;
+	
+	for (int i = 0; i < 100; i++) {
+		float st = length(ray) * 0.1;
+		ray += normalize(rv) * st;
+		if (length(ray) < 1.) { hit = true; break; }
+		rv += -normalize(ray) * -type / exp(dot(ray,ray)) * st;
+		em += st * smoothstep(1.5,1.2,length(ray)) * 0.2;
+	}
+	
+	vec4 k = PROJECTION_MATRIX * vec4(rv*1000.0, 1.0);
+	k /= k.z;
+	vec2 k2 = (k.xy + 1.) / 2.;
+
+	vec3 col = hit ? vec3(type*0.5+0.5) : texture(screen_texture, k2).rgb;
+	col += vec3(0.3,0.0,1.0) * max(em - 0.1,0.);
+	ALBEDO = col;
+}