New option to send canvas to render buffer

allows to use 3D environment effects for post processing such as Glow,
Bloom, HDR, etc. in 2D.

2 files changed, 37 insertions, 17 deletions

diff --git a/drivers/gles2/rasterizer_gles2.cpp b/drivers/gles2/rasterizer_gles2.cpp
index 49fae098a8..a21b0775e9 100644
--- a/drivers/gles2/rasterizer_gles2.cpp
+++ b/drivers/gles2/rasterizer_gles2.cpp
@@ -4288,7 +4288,7 @@ void RasterizerGLES2::capture_viewport(Image* r_capture) {
 
 void RasterizerGLES2::clear_viewport(const Color& p_color) {
 
-	if (current_rt) {
+	if (current_rt || using_canvas_bg) {
 
 		glScissor( 0, 0, viewport.width, viewport.height );
 	} else {
@@ -6944,7 +6944,7 @@ void RasterizerGLES2::_draw_tex_bg() {
 
 	RID texture;
 
-	if (current_env->bg_mode==VS::ENV_BG_TEXTURE || current_env->bg_mode==VS::ENV_BG_TEXTURE_RGBE) {
+	if (current_env->bg_mode==VS::ENV_BG_TEXTURE) {
 		texture=current_env->bg_param[VS::ENV_BG_PARAM_TEXTURE];
 	} else {
 		texture=current_env->bg_param[VS::ENV_BG_PARAM_CUBEMAP];
@@ -6961,25 +6961,20 @@ void RasterizerGLES2::_draw_tex_bg() {
 
 	copy_shader.set_conditional(CopyShaderGLES2::USE_ENERGY,true);
 
-	if (current_env->bg_mode==VS::ENV_BG_TEXTURE || current_env->bg_mode==VS::ENV_BG_TEXTURE_RGBE) {
+	if (current_env->bg_mode==VS::ENV_BG_TEXTURE) {
 		copy_shader.set_conditional(CopyShaderGLES2::USE_CUBEMAP,false);
 
 	} else {
 		copy_shader.set_conditional(CopyShaderGLES2::USE_CUBEMAP,true);
 	}
 
-	if (current_env->bg_mode==VS::ENV_BG_CUBEMAP_RGBE || current_env->bg_mode==VS::ENV_BG_TEXTURE_RGBE) {
-		copy_shader.set_conditional(CopyShaderGLES2::USE_RGBE,true);
-	} else {
-		copy_shader.set_conditional(CopyShaderGLES2::USE_RGBE,false);
-	}
 
 	copy_shader.set_conditional(CopyShaderGLES2::USE_CUSTOM_ALPHA,true);
 
 
 	copy_shader.bind();
 
-	if (current_env->bg_mode==VS::ENV_BG_TEXTURE || current_env->bg_mode==VS::ENV_BG_TEXTURE_RGBE) {
+	if (current_env->bg_mode==VS::ENV_BG_TEXTURE) {
 		glUniform1i( copy_shader.get_uniform_location(CopyShaderGLES2::SOURCE),0);
 	} else {
 		glUniform1i( copy_shader.get_uniform_location(CopyShaderGLES2::SOURCE_CUBE),0);
@@ -7006,7 +7001,7 @@ void RasterizerGLES2::_draw_tex_bg() {
 		Vector3( 0, 0, 0)
 	};
 
-	if (current_env->bg_mode==VS::ENV_BG_TEXTURE || current_env->bg_mode==VS::ENV_BG_TEXTURE_RGBE) {
+	if (current_env->bg_mode==VS::ENV_BG_TEXTURE) {
 
 		//regular texture
 		//adjust aspect
@@ -7076,7 +7071,7 @@ void RasterizerGLES2::end_scene() {
 	if (framebuffer.active) {
 
 		//detect when to use the framebuffer object
-		if (texscreen_used || framebuffer.scale!=1) {
+		if (using_canvas_bg || texscreen_used || framebuffer.scale!=1) {
 			use_fb=true;
 		} else if (current_env) {
 			use_fb=false;
@@ -7128,6 +7123,7 @@ void RasterizerGLES2::end_scene() {
 
 		switch(current_env->bg_mode) {
 
+			case VS::ENV_BG_CANVAS:
 			case VS::ENV_BG_KEEP: {
 				//copy from framebuffer if framebuffer
 				glClear(GL_DEPTH_BUFFER_BIT);
@@ -7140,7 +7136,7 @@ void RasterizerGLES2::end_scene() {
 					bgcolor = current_env->bg_param[VS::ENV_BG_PARAM_COLOR];
 				else
 					bgcolor = Globals::get_singleton()->get("render/default_clear_color");
-				bgcolor = _convert_color(bgcolor);
+			bgcolor = _convert_color(bgcolor);
 				float a = use_fb ? float(current_env->bg_param[VS::ENV_BG_PARAM_GLOW]) : 1.0;
 				glClearColor(bgcolor.r,bgcolor.g,bgcolor.b,a);
 				_glClearDepth(1.0);
@@ -7148,9 +7144,7 @@ void RasterizerGLES2::end_scene() {
 
 			} break;
 			case VS::ENV_BG_TEXTURE:
-			case VS::ENV_BG_CUBEMAP:
-			case VS::ENV_BG_TEXTURE_RGBE:
-			case VS::ENV_BG_CUBEMAP_RGBE: {
+			case VS::ENV_BG_CUBEMAP: {
 
 
 				glClear(GL_DEPTH_BUFFER_BIT);
@@ -7369,8 +7363,12 @@ void RasterizerGLES2::end_scene() {
 		_debug_shadows();
 	}
 //	_debug_luminances();
-	_debug_samplers();
+//	_debug_samplers();
 
+	if (using_canvas_bg) {
+		using_canvas_bg=false;
+		glColorMask(1,1,1,1); //don't touch alpha
+	}
 
 }
 void RasterizerGLES2::end_shadow_map() {
@@ -7839,8 +7837,26 @@ void RasterizerGLES2::flush_frame() {
 
 /* CANVAS API */
 
+void RasterizerGLES2::begin_canvas_bg() {
+
+	if (framebuffer.active) {
+		using_canvas_bg=true;
+		glBindFramebuffer(GL_FRAMEBUFFER, framebuffer.fbo);
+		glViewport( 0,0,viewport.width , viewport.height );
+	} else {
+		using_canvas_bg=false;
+	}
+
+}
+
 void RasterizerGLES2::canvas_begin() {
 
+
+	if (using_canvas_bg) {
+		glBindFramebuffer(GL_FRAMEBUFFER, framebuffer.fbo);
+		glColorMask(1,1,1,0); //don't touch alpha
+	}
+
 	glDisable(GL_CULL_FACE);
 	glDisable(GL_DEPTH_TEST);
 	glDisable(GL_SCISSOR_TEST);
@@ -10567,7 +10583,7 @@ void RasterizerGLES2::init() {
 	glBindBuffer(GL_ARRAY_BUFFER,0); //unbind
 
 
-
+	using_canvas_bg=false;
 	_update_framebuffer();
 	DEBUG_TEST_ERROR("Initializing");
 }
diff --git a/drivers/gles2/rasterizer_gles2.h b/drivers/gles2/rasterizer_gles2.h
index f09714f50c..b7895ad82e 100644
--- a/drivers/gles2/rasterizer_gles2.h
+++ b/drivers/gles2/rasterizer_gles2.h
@@ -677,6 +677,7 @@ class RasterizerGLES2 : public Rasterizer {
 			bg_param[VS::ENV_BG_PARAM_ENERGY]=1.0;
 			bg_param[VS::ENV_BG_PARAM_SCALE]=1.0;
 			bg_param[VS::ENV_BG_PARAM_GLOW]=0.0;
+			bg_param[VS::ENV_BG_PARAM_CANVAS_MAX_LAYER]=0;
 
 			for(int i=0;i<VS::ENV_FX_MAX;i++)
 				fx_enabled[i]=false;
@@ -1258,6 +1259,7 @@ class RasterizerGLES2 : public Rasterizer {
 	void _process_hdr();
 	void _draw_tex_bg();
 
+	bool using_canvas_bg;
 	Size2 window_size;
 	VS::ViewportRect viewport;
 	double last_time;
@@ -1600,6 +1602,8 @@ public:
 
 	/* CANVAS API */
 
+	virtual void begin_canvas_bg();
+
 	virtual void canvas_begin();
 	virtual void canvas_disable_blending();