diff --git a/lib/render/gat.ts b/lib/render/gat.ts
index 716ee84..944b898 100644
--- a/lib/render/gat.ts
+++ b/lib/render/gat.ts
@@ -74,24 +74,22 @@ export const renderGAT = (gl: WebGLRenderingContext, gat: GAT) => {
   console.log("center", center);
 
   const model = mat4.create();
-  mat4.identity(model);
   mat4.translate(
     model,
     model,
-    vec3.fromValues(-centerX, -maxAltitude - 10, -centerZ)
+    vec3.fromValues(-camera[0], -camera[1], -camera[2])
   );
 
   const view = mat4.create();
-  mat4.identity(view);
   mat4.rotateX(view, view, -Math.PI / 2);
   // mat4.lookAt(view, camera, center, UP);
 
   const modelview = model;
-  mat4.multiply(modelview, model, view);
+  mat4.multiply(modelview, view, model);
 
   const perspective = mat4.create();
   const aspect = gl.canvas.clientWidth / gl.canvas.clientHeight;
-  mat4.perspective(perspective, Math.PI / 4, aspect, -10, -2000);
+  mat4.perspective(perspective, Math.PI / 4, aspect, -0.5, 1000);
 
   const matrix = mat4.create();
   mat4.multiply(matrix, modelview, perspective);
@@ -101,11 +99,13 @@ export const renderGAT = (gl: WebGLRenderingContext, gat: GAT) => {
 
   printMat4("model", model);
   printMat4("view", view);
-  printMat4("model + view", modelview);
+  printMat4("view * model", modelview);
   printMat4("projection", perspective);
-  printMat4("model + view + projection", matrix);
+  printMat4("projection * view * model", matrix);
 
   const origin = vec4.create();
+  vec4.transformMat4(origin, ORIGIN, model);
+  console.log("origin (model)", origin);
   vec4.transformMat4(origin, ORIGIN, modelview);
   console.log("origin (modelview)", origin);
   vec4.transformMat4(origin, ORIGIN, matrix);
@@ -138,17 +138,21 @@ export const renderGAT = (gl: WebGLRenderingContext, gat: GAT) => {
 
   let failCount = 0;
   for (let i = 0; i < vertices.length / 3; ++i) {
-    const vec = vec3.fromValues(vertices[i], vertices[i + 1], vertices[i + 2]);
+    const vec = vec4.fromValues(
+      vertices[i],
+      vertices[i + 1],
+      vertices[i + 2],
+      1
+    );
     const result = checkPixelCoord(vec, matrix);
     if (result) {
       if (failCount < 10) {
-        console.log(vec);
-        console.log(result);
+        console.log("vertex clipped, (pre-xform)", vec, "(post-xform)", result);
       }
       failCount++;
     }
   }
-  console.log("failCount", failCount);
+  console.log("clipCount", failCount);
   console.log("totalCount", vertices.length / 3);
 
   const vertexBuffer = gl.createBuffer();
@@ -167,9 +171,9 @@ export const renderGAT = (gl: WebGLRenderingContext, gat: GAT) => {
   gl.drawArrays(gl.TRIANGLES, 0, vertices.length / 3);
 };
 
-const checkPixelCoord = (x: vec3, mat: mat4): vec4 | null => {
-  const vec = vec4.fromValues(x[0], x[1], x[2], 1);
-  vec4.transformMat4(vec, vec, mat);
+const checkPixelCoord = (x: vec4, mat: mat4): vec4 | null => {
+  const vec = vec4.create();
+  vec4.transformMat4(vec, x, mat);
   for (let i = 0; i < vec.length; ++i) {
     if (Math.abs(vec[i]) >= 1) {
       return vec;