From 743e2595ac191f014e3da8a100ced524f53aabfd Mon Sep 17 00:00:00 2001
From: Mike Kazantsev <mk.fraggod@gmail.com>
Date: Wed, 25 Jul 2018 15:34:35 +0500
Subject: [PATCH] Add layer option to evgInit

---
 example/hello.c | 4 ++--
 python/evg.py   | 2 +-
 python/hello.py | 2 +-
 src/libshapes.c | 3 ++-
 src/libshapes.h | 2 +-
 src/oglinit.c   | 2 +-
 src/oglinit.h   | 3 +++
 7 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/example/hello.c b/example/hello.c
index 3208ce6..61a9c87 100644
--- a/example/hello.c
+++ b/example/hello.c
@@ -14,8 +14,8 @@ int main() {
     /* We have to initialise the OpenVG canvas and renderer by using
      * `init(&w, &h)`.
      */
-    evgInit(&width, &height);
-    evgBegin(width, height);
+    evgInit(&width, &height, 0);
+    evgBegin();
     {
         evgBackground(0, 0, 0);
         evgFill(44, 77, 232, 1);
diff --git a/python/evg.py b/python/evg.py
index 4303ca8..ce5875f 100644
--- a/python/evg.py
+++ b/python/evg.py
@@ -38,7 +38,7 @@ class LibShapes(object):
 		evgSaveEnd(char *)
 		evgBackground(unsigned int, unsigned int, unsigned int)
 		evgBackgroundRGB(unsigned int, unsigned int, unsigned int, VGfloat)
-		evgInit(int *, int *)
+		evgInit(int *, int *, int)
 		evgFinish()
 		evgSetFill(VGfloat[4])
 		evgSetStroke(VGfloat[4])
diff --git a/python/hello.py b/python/hello.py
index 14cde62..098c164 100644
--- a/python/hello.py
+++ b/python/hello.py
@@ -7,7 +7,7 @@
 evg = LibShapes()
 
 w, h = evg.c_int(), evg.c_int()
-evg.init(w, h)
+evg.init(w, h, 0)
 evg.begin()
 
 evg.background(0, 0, 0)
diff --git a/src/libshapes.c b/src/libshapes.c
index 1e78921..289084c 100644
--- a/src/libshapes.c
+++ b/src/libshapes.c
@@ -249,13 +249,14 @@ void evgInitWindowSize(int x, int y, unsigned int w, unsigned int h) {
 }
 
 // init sets the system to its initial state
-void evgInit(int *w, int *h) {
+void evgInit(int *w, int *h, int layer) {
     bcm_host_init();
     memset(state, 0, sizeof(*state));
     state->window_x = init_x;
     state->window_y = init_y;
     state->window_width = init_w;
     state->window_height = init_h;
+    state->layer = (int32_t) layer;
     oglinit(state);
     SansTypeface = loadfont(DejaVuSans_glyphPoints,
                 DejaVuSans_glyphPointIndices,
diff --git a/src/libshapes.h b/src/libshapes.h
index 35c788b..9bde1f4 100644
--- a/src/libshapes.h
+++ b/src/libshapes.h
@@ -35,7 +35,7 @@ extern "C" {
 	extern void evgSaveEnd(const char *);
 	extern void evgBackground(unsigned int, unsigned int, unsigned int);
 	extern void evgBackgroundRGB(unsigned int, unsigned int, unsigned int, VGfloat);
-	extern void evgInit(int *, int *);
+	extern void evgInit(int *, int *, int);
 	extern void evgFinish();
 	extern void evgSetFill(VGfloat[4]);
 	extern void evgSetStroke(VGfloat[4]);
diff --git a/src/oglinit.c b/src/oglinit.c
index a880d15..39b0250 100644
--- a/src/oglinit.c
+++ b/src/oglinit.c
@@ -132,7 +132,7 @@ void oglinit(EVG_STATE_T * state) {
     dispman_display = vc_dispmanx_display_open(0 /* LCD */ );
     dispman_update = vc_dispmanx_update_start(0);
 
-    dispman_element = vc_dispmanx_element_add(dispman_update, dispman_display, 0 /*layer */ , &dst_rect, 0 /*src */ ,
+    dispman_element = vc_dispmanx_element_add(dispman_update, dispman_display, state->layer, &dst_rect, 0 /*src */ ,
                           &src_rect, DISPMANX_PROTECTION_NONE, &alpha, 0 /*clamp */ ,
                           0 /*transform */ );
 
diff --git a/src/oglinit.h b/src/oglinit.h
index d3d27af..a3c2160 100644
--- a/src/oglinit.h
+++ b/src/oglinit.h
@@ -22,6 +22,9 @@ typedef struct {
     /** Window height, in pixels. */
     uint32_t window_height;
 
+    /** Layer on which to draw stuff. */
+    int32_t layer;
+
     DISPMANX_ELEMENT_HANDLE_T element;
 
     // EGL data