diff --git a/internal/graphics/opengl/context_desktop.go b/internal/graphics/opengl/context_desktop.go
index 66783ca6e..c5167bca6 100644
--- a/internal/graphics/opengl/context_desktop.go
+++ b/internal/graphics/opengl/context_desktop.go
@@ -42,8 +42,7 @@ type AttribLocation int32
 
 type ProgramID uint32
 
-// TODO: This should be a method?
-func GetProgramID(p Program) ProgramID {
+func (p Program) ID() ProgramID {
 	return ProgramID(p)
 }
 
diff --git a/internal/graphics/opengl/context_js.go b/internal/graphics/opengl/context_js.go
index 0283021bb..f0e04f4d1 100644
--- a/internal/graphics/opengl/context_js.go
+++ b/internal/graphics/opengl/context_js.go
@@ -58,7 +58,7 @@ type AttribLocation int
 
 type ProgramID int
 
-func GetProgramID(p Program) ProgramID {
+func (p Program) ID() ProgramID {
 	return ProgramID(p.Get("__ebiten_programId").Int())
 }
 
diff --git a/internal/graphics/opengl/context_mobile.go b/internal/graphics/opengl/context_mobile.go
index ebcd485bb..044e08566 100644
--- a/internal/graphics/opengl/context_mobile.go
+++ b/internal/graphics/opengl/context_mobile.go
@@ -43,7 +43,7 @@ type AttribLocation mgl.Attrib
 
 type ProgramID uint32
 
-func GetProgramID(p Program) ProgramID {
+func (p Program) ID() ProgramID {
 	return ProgramID(p.Value)
 }
 
diff --git a/internal/graphics/opengl/locationcache.go b/internal/graphics/opengl/locationcache.go
index 758203650..8213f06a3 100644
--- a/internal/graphics/opengl/locationcache.go
+++ b/internal/graphics/opengl/locationcache.go
@@ -26,7 +26,7 @@ type UniformLocationGetter interface {
 // TODO: Rename these functions not to be confusing
 
 func GetUniformLocation(g UniformLocationGetter, p Program, location string) UniformLocation {
-	id := GetProgramID(p)
+	id := p.ID()
 	if _, ok := uniformLocationCache[id]; !ok {
 		uniformLocationCache[id] = map[string]UniformLocation{}
 	}
@@ -43,7 +43,7 @@ type AttribLocationGetter interface {
 }
 
 func GetAttribLocation(g AttribLocationGetter, p Program, location string) AttribLocation {
-	id := GetProgramID(p)
+	id := p.ID()
 	if _, ok := attribLocationCache[id]; !ok {
 		attribLocationCache[id] = map[string]AttribLocation{}
 	}