diff -r 4f32c7755138 -r f72b80448413 src/shader.c
--- a/src/shader.c	Fri Jul 25 18:50:36 2025 +0200
+++ b/src/shader.c	Fri Jul 25 18:54:51 2025 +0200
@@ -225,10 +225,12 @@
     if (asc_shader_invalid(shader)) {
         asc_active_glctx->active_program = 0;
         glUseProgram(0);
+        return -1;
+    }
+    if (asc_active_glctx->active_program == shader->gl_id) {
+        // already using this shader - continue
         return 0;
     }
-    if (asc_active_glctx->active_program == shader->gl_id) return 0;
-    if (asc_shader_invalid(shader)) return -1;
     asc_active_glctx->active_program = shader->gl_id;
     glUseProgram(shader->gl_id);
     glUniformMatrix4fv(shader->projection, 1, GL_FALSE, camera->projection);