gles2: change context when it is not current

Texture functions, that create and manipulate textures should switch
the current context if necessary.

thanks to: @emersion

Fixes #934

include/render/gles2.h

@@ -88,7 +88,7 @@ const struct wlr_gles2_pixel_format *get_gles2_format_from_wl(
 	enum wl_shm_format fmt);
 const enum wl_shm_format *get_gles2_formats(size_t *len);
 
-struct wlr_gles2_texture *get_gles2_texture_in_context(
+struct wlr_gles2_texture *gles2_get_texture(
 	struct wlr_texture *wlr_texture);
 
 void push_gles2_marker(const char *file, const char *func);

render/gles2/renderer.c

@@ -116,7 +116,7 @@ static bool gles2_render_texture_with_matrix(struct wlr_renderer *wlr_renderer,
 	struct wlr_gles2_renderer *renderer =
 		gles2_get_renderer_in_context(wlr_renderer);
 	struct wlr_gles2_texture *texture =
-		get_gles2_texture_in_context(wlr_texture);
+		gles2_get_texture(wlr_texture);
 
 	struct wlr_gles2_tex_shader *shader = NULL;
 	GLenum target = 0;
@@ -213,7 +213,7 @@ static const enum wl_shm_format *gles2_renderer_formats(
 static bool gles2_resource_is_wl_drm_buffer(struct wlr_renderer *wlr_renderer,
 		struct wl_resource *resource) {
 	struct wlr_gles2_renderer *renderer =
-		gles2_get_renderer_in_context(wlr_renderer);
+		gles2_get_renderer(wlr_renderer);
 
 	if (!eglQueryWaylandBufferWL) {
 		return false;
@@ -227,7 +227,7 @@ static bool gles2_resource_is_wl_drm_buffer(struct wlr_renderer *wlr_renderer,
 static void gles2_wl_drm_buffer_get_size(struct wlr_renderer *wlr_renderer,
 		struct wl_resource *buffer, int *width, int *height) {
 	struct wlr_gles2_renderer *renderer =
-		gles2_get_renderer_in_context(wlr_renderer);
+		gles2_get_renderer(wlr_renderer);
 
 	if (!eglQueryWaylandBufferWL) {
 		return;
@@ -323,7 +323,7 @@ static struct wlr_texture *gles2_texture_from_dmabuf(
 static void gles2_init_wl_display(struct wlr_renderer *wlr_renderer,
 		struct wl_display *wl_display) {
 	struct wlr_gles2_renderer *renderer =
-		gles2_get_renderer_in_context(wlr_renderer);
+		gles2_get_renderer(wlr_renderer);
 	if (!wlr_egl_bind_display(renderer->egl, wl_display)) {
 		wlr_log(WLR_INFO, "failed to bind wl_display to EGL");
 	}

render/gles2/texture.c

@@ -16,7 +16,7 @@
 
 static const struct wlr_texture_impl texture_impl;
 
-static struct wlr_gles2_texture *gles2_get_texture(
+struct wlr_gles2_texture *gles2_get_texture(
 		struct wlr_texture *wlr_texture) {
 	assert(wlr_texture->impl == &texture_impl);
 	return (struct wlr_gles2_texture *)wlr_texture;
@@ -25,7 +25,9 @@ static struct wlr_gles2_texture *gles2_get_texture(
 struct wlr_gles2_texture *get_gles2_texture_in_context(
 		struct wlr_texture *wlr_texture) {
 	struct wlr_gles2_texture *texture = gles2_get_texture(wlr_texture);
-	assert(wlr_egl_is_current(texture->egl));
+	if (!wlr_egl_is_current(texture->egl)) {
+		wlr_egl_make_current(texture->egl, EGL_NO_SURFACE, NULL);
+	}
 	return texture;
 }
 
@@ -143,7 +145,9 @@ static const struct wlr_texture_impl texture_impl = {
 struct wlr_texture *wlr_gles2_texture_from_pixels(struct wlr_egl *egl,
 		enum wl_shm_format wl_fmt, uint32_t stride, uint32_t width,
 		uint32_t height, const void *data) {
-	assert(wlr_egl_is_current(egl));
+	if (!wlr_egl_is_current(egl)) {
+		wlr_egl_make_current(egl, EGL_NO_SURFACE, NULL);
+	}
 
 	const struct wlr_gles2_pixel_format *fmt = get_gles2_format_from_wl(wl_fmt);
 	if (fmt == NULL) {
@@ -180,7 +184,9 @@ struct wlr_texture *wlr_gles2_texture_from_pixels(struct wlr_egl *egl,
 
 struct wlr_texture *wlr_gles2_texture_from_wl_drm(struct wlr_egl *egl,
 		struct wl_resource *data) {
-	assert(wlr_egl_is_current(egl));
+	if (!wlr_egl_is_current(egl)) {
+		wlr_egl_make_current(egl, EGL_NO_SURFACE, NULL);
+	}
 
 	if (!glEGLImageTargetTexture2DOES) {
 		return NULL;
@@ -239,7 +245,9 @@ struct wlr_texture *wlr_gles2_texture_from_wl_drm(struct wlr_egl *egl,
 
 struct wlr_texture *wlr_gles2_texture_from_dmabuf(struct wlr_egl *egl,
 		struct wlr_dmabuf_attributes *attribs) {
-	assert(wlr_egl_is_current(egl));
+	if (!wlr_egl_is_current(egl)) {
+		wlr_egl_make_current(egl, EGL_NO_SURFACE, NULL);
+	}
 
 	if (!glEGLImageTargetTexture2DOES) {
 		return NULL;