X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=equations.vert;h=731e1599170499c6776f4b37b05d4b0ef8e58b91;hb=c015224d38abb896d92c55f1b4517f0600828f68;hp=6ace5775e0017f69261dd20f35a9ca68602c651d;hpb=632cf18d06090795ea725117b4c48bd230dda72f;p=nageru

diff --git a/equations.vert b/equations.vert
index 6ace577..731e159 100644
--- a/equations.vert
+++ b/equations.vert
@@ -1,9 +1,12 @@
 #version 450 core
+#extension GL_ARB_shader_viewport_layer_array : require
 
 layout(location=0) in vec2 position;
-out vec2 tc, tc_left, tc_down;
+out vec3 tc0, tc_left0, tc_down0;
+out vec3 tc1, tc_left1, tc_down1;
+out float line_offset;
 
-uniform sampler2D diffusivity_tex;
+uniform sampler2DArray diffusivity_tex;
 
 void main()
 {
@@ -14,7 +17,22 @@ void main()
 	//   0.000  0.000 -2.000 -1.000
 	//   0.000  0.000  0.000  1.000
 	gl_Position = vec4(2.0 * position.x - 1.0, 2.0 * position.y - 1.0, -1.0, 1.0);
-	tc = position;
-	tc_left = vec2(tc.x - 0.5f / textureSize(diffusivity_tex, 0).x, tc.y);
-	tc_down = vec2(tc.x, tc.y - 0.5f / textureSize(diffusivity_tex, 0).y);
+	gl_Layer = gl_InstanceID;
+
+	const vec2 half_texel = 0.5f / textureSize(diffusivity_tex, 0).xy;
+
+	vec2 tc = position;
+	vec2 tc_left = vec2(tc.x - half_texel.x, tc.y);
+	vec2 tc_down = vec2(tc.x, tc.y - half_texel.y);
+
+	// Adjust for different texel centers.
+	tc0 = vec3(tc.x - half_texel.x, tc.y, gl_InstanceID);
+	tc_left0 = vec3(tc_left.x - half_texel.x, tc_left.y, gl_InstanceID);
+	tc_down0 = vec3(tc_down.x - half_texel.x, tc_down.y, gl_InstanceID);
+
+	tc1 = vec3(tc.x + half_texel.x, tc.y, gl_InstanceID);
+	tc_left1 = vec3(tc_left.x + half_texel.x, tc_left.y, gl_InstanceID);
+	tc_down1 = vec3(tc_down.x + half_texel.x, tc_down.y, gl_InstanceID);
+
+	line_offset = position.y * textureSize(diffusivity_tex, 0).y - 0.5f;
 }