Shader:hasBlock; Shader:sendBlock errors on missing block;

src/api/l_graphics_shader.c

@@ -197,6 +197,13 @@ static int l_lovrShaderHasUniform(lua_State* L) {
   return 1;
 }
 
+static int l_lovrShaderHasBlock(lua_State* L) {
+  Shader* shader = luax_checktype(L, 1, Shader);
+  const char* name = luaL_checkstring(L, 2);
+  lua_pushboolean(L, lovrShaderHasBlock(shader, name));
+  return 1;
+}
+
 static int l_lovrShaderSend(lua_State* L) {
   Shader* shader = luax_checktype(L, 1, Shader);
   const char* name = luaL_checkstring(L, 2);
@@ -222,6 +229,7 @@ static int l_lovrShaderSend(lua_State* L) {
 static int l_lovrShaderSendBlock(lua_State* L) {
   Shader* shader = luax_checktype(L, 1, Shader);
   const char* name = luaL_checkstring(L, 2);
+  lovrAssert(lovrShaderHasBlock(shader, name), "Unknown shader block '%s'", name);
   ShaderBlock* block = luax_checktype(L, 3, ShaderBlock);
   UniformAccess access = luaL_checkoption(L, 4, "readwrite", UniformAccesses);
   Buffer* buffer = lovrShaderBlockGetBuffer(block);
@@ -251,6 +259,7 @@ static int l_lovrShaderSendImage(lua_State* L) {
 const luaL_Reg lovrShader[] = {
   { "getType", l_lovrShaderGetType },
   { "hasUniform", l_lovrShaderHasUniform },
+  { "hasBlock", l_lovrShaderHasBlock },
   { "send", l_lovrShaderSend },
   { "sendBlock", l_lovrShaderSendBlock },
   { "sendImage", l_lovrShaderSendImage },

src/modules/graphics/shader.c

@@ -86,6 +86,10 @@ bool lovrShaderHasUniform(Shader* shader, const char* name) {
   return map_get(&shader->uniformMap, hash64(name, strlen(name))) != MAP_NIL;
 }
 
+bool lovrShaderHasBlock(Shader* shader, const char* name) {
+  return map_get(&shader->blockMap, hash64(name, strlen(name))) != MAP_NIL;
+}
+
 const Uniform* lovrShaderGetUniform(Shader* shader, const char* name) {
   uint64_t index = map_get(&shader->uniformMap, hash64(name, strlen(name)));
   return index == MAP_NIL ? NULL : &shader->uniforms.data[index];

src/modules/graphics/shader.h

@@ -133,6 +133,7 @@ void lovrShaderDestroy(void* ref);
 ShaderType lovrShaderGetType(Shader* shader);
 int lovrShaderGetAttributeLocation(Shader* shader, const char* name);
 bool lovrShaderHasUniform(Shader* shader, const char* name);
+bool lovrShaderHasBlock(Shader* shader, const char* name);
 const Uniform* lovrShaderGetUniform(Shader* shader, const char* name);
 void lovrShaderSetFloats(Shader* shader, const char* name, float* data, int start, int count);
 void lovrShaderSetInts(Shader* shader, const char* name, int* data, int start, int count);