Add MVP projection passed through push constant

gpu.h

@@ -6,10 +6,21 @@
 
 #define SWAPCHAIN_IMG_BUFFER_SIZE 4
 
+typedef float vec2_t[3];
+typedef float vec3_t[3];
+typedef float mat4_t[16];
+
 typedef struct {
-	float position[2], colour[3];
+	vec2_t position;
+	vec3_t colour;
 } vertex_t;
 
+typedef struct {
+	mat4_t model;
+	mat4_t view;
+	mat4_t proj;
+} mvp_t;
+
 typedef struct {
 	VkInstance inst;
 	VkSurfaceKHR surface;
@@ -49,6 +60,6 @@ typedef struct {
 
 void gpu_init(gpu_ctx_t *ctx, const gpu_config_t *config);
 void gpu_cleanup(const gpu_ctx_t *ctx);
-void gpu_render(const gpu_ctx_t *ctx);
+void gpu_render(const gpu_ctx_t *ctx, const mvp_t *mvp);
 
 #endif