diff --git a/scripts/base.js b/scripts/base.js
index 7ff195c..8ac389c 100644
--- a/scripts/base.js
+++ b/scripts/base.js
@@ -1534,6 +1534,7 @@ yaml.tojson = function (yaml) {
   yaml = yaml.replace(/,}/g, "}");
   yaml = yaml.replace(/,]/g, "]");
   yaml = yaml.replace(/,"[^"]+"\:,/g, ",");
+  yaml = yaml.replace(/,"[^"]+"\:}/g, "}");  
   return yaml;
 };
 
diff --git a/scripts/components.js b/scripts/components.js
index 4d999b5..9e6d5be 100644
--- a/scripts/components.js
+++ b/scripts/components.js
@@ -290,7 +290,7 @@ SpriteAnim.gif = function (path) {
   var anim = {};
   anim.frames = [];
   anim.path = path;
-  var tex = game.texture(path);
+  var tex = game.texture(path).texture;
   var frames = tex.frames;
   if (frames === 1) return undefined;
   var yslice = 1 / frames;
diff --git a/scripts/render.js b/scripts/render.js
index 3d0552c..4719d67 100644
--- a/scripts/render.js
+++ b/scripts/render.js
@@ -137,15 +137,15 @@ var base_pipeline = {
     bias_clamp: 0
   },
   stencil: {
-    enabled: false,
+    enabled: true,
     front: {
-      compare: compare.always,
+      compare: compare.equal,
       fail_op: stencilop.keep,
       depth_fail_op: stencilop.keep,
       pass_op: stencilop.keep
     },
     back: {
-      compare: compare.always,
+      compare: compare.equal,
       fail_op: stencilop.keep,
       depth_fail_op: stencilop.keep,
       pass_op: stencilop.keep
@@ -184,18 +184,40 @@ render.use_pipeline = function use_pipeline(pipeline)
 
 }
 
-// When changing a shader, everything must wipe
-render.use_shader = function use_shader(shader) {
+var pipe_shaders = new WeakMap();
+
+// Uses the shader with the specified pipeline. If none specified, uses the base pipeline
+render.use_shader = function use_shader(shader, pipeline) {
+  pipeline ??= base_pipeline;
   if (typeof shader === "string") shader = make_shader(shader);
   if (cur.shader === shader) return;
+  
+  if (!pipe_shaders.has(shader)) pipe_shaders.set(shader, new WeakMap());
+  var shader_pipelines = pipe_shaders.get(shader);
+  if (!shader_pipelines.has(pipeline)) {
+    var new_pipeline = render.make_pipeline(shader,pipeline);
+    shader_pipelines.set(pipeline, new_pipeline);
+  }
+  
+  var use_pipeline = shader_pipelines.get(pipeline);
+  if (cur.shader === shader && cur.pipeline === use_pipeline) return;
+  
   cur.shader = shader;
   cur.bind = undefined;
   cur.mesh = undefined;
   cur.ssbo = undefined;
-  render.setpipeline(shader.pipe);
+  cur.images = [];
+  cur.pipeline = use_pipeline;
+  
+  // Grab or create a pipeline obj that utilizes the specific shader and pipeline
+  render.setpipeline(use_pipeline);
   shader_globals(cur.shader);
 };
 
+render.use_pipeline = function use_pipeline(pipeline) {
+
+}
+
 render.use_mat = function use_mat(mat) {
   if (!cur.shader) return;
   if (cur.mat === mat) return;
@@ -311,7 +333,6 @@ render.hotreload = function () {
     shader_times[i] = io.mod(i);
     var obj = create_shader_obj(i);
     obj = obj[os.sys()];
-    obj.pipe = render.pipeline(obj, base_pipeline);
     var old = shader_cache[i];
     Object.assign(shader_cache[i], obj);
     cur.bind = undefined;
@@ -439,8 +460,6 @@ function make_shader(shader, pipe) {
     var shaderobj = json.decode(io.slurp(writejson));
     var obj = shaderobj[os.sys()];
     
-    pipe ??= base_pipeline;
-    obj.pipe = render.pipeline(obj, pipe);
     shader_cache[file] = obj;
     shader_times[file] = io.mod(file);
     return obj;
@@ -451,7 +470,6 @@ function make_shader(shader, pipe) {
   var compiled = create_shader_obj(file);
   io.slurpwrite(writejson, json.encode(compiled));
   var obj = compiled[os.sys()];
-  obj.pipe = render.pipeline(obj, base_pipeline);
 
   shader_cache[file] = obj;
   shader_times[file] = io.mod(file);
@@ -600,7 +618,6 @@ var slice9shader;
 var parshader;
 var spritessboshader;
 var polyssboshader;
-var maskshader;
 var sprite_ssbo;
 
 render.init = function () {
@@ -609,13 +626,13 @@ render.init = function () {
   spritessboshader = make_shader("shaders/sprite_ssbo.cg");
   var postpipe = Object.create(base_pipeline);
   postpipe.cull = cull_map.none;
+  postpipe.primitive = primitive_map.triangle;
   render.postshader = make_shader("shaders/simplepost.cg", postpipe);
   slice9shader = make_shader("shaders/9slice.cg");
   circleshader = make_shader("shaders/circle.cg");
   polyshader = make_shader("shaders/poly.cg");
   parshader = make_shader("shaders/baseparticle.cg");
   polyssboshader = make_shader("shaders/poly_ssbo.cg");
-  maskshader = make_shader('shaders/mask.cg');
   poly_ssbo = render.make_textssbo();
   sprite_ssbo = render.make_textssbo();
 
@@ -882,11 +899,46 @@ render.floodmask = function(val)
   render.use_mat({});
 }
 
+var stencil_write = {
+  compare: compare.always,
+  fail_op: stencilop.replace,
+  depth_fail_op:stencilop.replace,
+  pass_op: stencilop.replace
+};
+
+function stencil_writer(ref)
+{
+  var pipe = Object.create(base_pipeline);
+  Object.assign(pipe, {
+    stencil: {
+      enabled: true,
+      front: stencil_write,
+      back: stencil_write,
+      write:true,
+      read:true,
+      ref:ref
+    },
+    write_mask: colormask.none
+  });
+}
+
+// objects by default draw where the stencil buffer is 0
+
+var pipe_stencil_on = stencil_writer(1);
+var pipe_stencil_off = stencil_writer(0);
+
+render.fillmask = function(on)
+{
+  var pipe = on ? pipe_stencil_on : pipe_stencil_off;
+  render.use_shader('shaders/screenfill.cg', pipe);
+  render.draw(shape.quad);
+} 
+
 render.mask = function mask(tex, pos, scale, rotation = 0)
 {
   if (typeof tex === 'string') tex = game.texture(tex);
 
-  render.use_shader(maskshader);
+  render.use_shader(spritessboshader, pipe_stencil_on);
   var t = os.make_transform();
   t.pos = pos;
   t.scale = scale;
@@ -1238,7 +1290,7 @@ prosperon.render = function () {
   prosperon.postvals.diffuse = prosperon.screencolor;
   
   render.use_mat(prosperon.postvals);
-  render.draw(os.backend() === "directx" ? shape.flipquad : shape.quad);
+  render.draw((os.backend() === "directx" || os.backend() === 'metal') ? shape.flipquad : shape.quad);
 
   profile.endreport("post process");
 
diff --git a/shaders/screenfill.cg b/shaders/screenfill.cg
new file mode 100644
index 0000000..98f7590
--- /dev/null
+++ b/shaders/screenfill.cg
@@ -0,0 +1,22 @@
+@vs vs
+in vec3 a_pos;
+
+void main()
+{
+  vec3 pos = a_pos;
+  pos -= 0.5;
+  pos *= 2;
+  gl_Position = vec4(pos.xy, 0, 1.0);
+}
+@end
+
+@fs fs
+out vec4 color;
+
+void main()
+{
+  color = vec4(1.0);
+}
+@end
+
+@program p vs fs
diff --git a/shaders/sprite_ssbo.cg b/shaders/sprite_ssbo.cg
index e20b39a..c3f2d25 100644
--- a/shaders/sprite_ssbo.cg
+++ b/shaders/sprite_ssbo.cg
@@ -47,6 +47,7 @@ void frag()
 {
   color = texture(sampler2D(diffuse,smp), uv);
   color *= shade;
+  if (color.a == 0.0) discard;
 }
 
 void main()
diff --git a/source/engine/jsffi.c b/source/engine/jsffi.c
index 8524e4a..e2f46aa 100644
--- a/source/engine/jsffi.c
+++ b/source/engine/jsffi.c
@@ -1012,7 +1012,7 @@ sg_blend_state js2blend(JSValue v)
   return blend;
 }
 
-JSC_CCALL(render_pipeline,
+JSC_CCALL(render_make_pipeline,
   sg_pipeline_desc p = {0};
   p.shader = js2shader(argv[0]);
   p.layout = js2layout(argv[0]);
@@ -1253,7 +1253,7 @@ static const JSCFunctionListEntry js_render_funcs[] = {
   MIST_FUNC_DEF(render, glue_pass, 0),
   MIST_FUNC_DEF(render, text_size, 3),
   MIST_FUNC_DEF(render, set_camera, 1),
-  MIST_FUNC_DEF(render, pipeline, 1),
+  MIST_FUNC_DEF(render, make_pipeline, 1),
   MIST_FUNC_DEF(render, setuniv3, 2),
   MIST_FUNC_DEF(render, setuniv, 2),
   MIST_FUNC_DEF(render, spdraw, 3),
diff --git a/source/engine/texture.h b/source/engine/texture.h
index cddb564..1ae5926 100644
--- a/source/engine/texture.h
+++ b/source/engine/texture.h
@@ -25,6 +25,7 @@ struct texture {
   simgui_image_t simgui;
   int width;
   int height;
+  HMM_Vec3 dimensions;
   unsigned char *data;
   int frames;
   int *delays;