diff --git a/include/cglm/project.h b/include/cglm/project.h
index 45f38a7..f52d3a0 100644
--- a/include/cglm/project.h
+++ b/include/cglm/project.h
@@ -124,7 +124,7 @@ glm_project(vec3 pos, mat4 m, vec4 vp, vec3 dest) {
  */
 CGLM_INLINE
 void
-glm_pickmatrix(vec3 center, vec2 size, vec4 vp, mat4 dest) {
+glm_pickmatrix(vec2 center, vec2 size, vec4 vp, mat4 dest) {
   mat4 res;
   vec3 v;
 
diff --git a/include/cglm/struct/project.h b/include/cglm/struct/project.h
index 130ff99..00f76ff 100644
--- a/include/cglm/struct/project.h
+++ b/include/cglm/struct/project.h
@@ -111,7 +111,7 @@ glms_project(vec3s pos, mat4s m, vec4s vp) {
  */
 CGLM_INLINE
 mat4s
-glms_pickmatrix(vec3s center, vec2s size, vec4s vp) {
+glms_pickmatrix(vec2s center, vec2s size, vec4s vp) {
   mat4s res;
   glm_pickmatrix(center.raw, size.raw, vp.raw, res.raw);
   return res;