Use raster versions of copy effects for 2D operations when using the mobile renderer

This PR implements a few basic copy operations in raster that weren't available before

3 files changed, 47 insertions, 32 deletions

diff --git a/servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl b/servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl
index cb06250cf2..31aabbe9d2 100644
--- a/servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl
@@ -53,30 +53,31 @@ void main() {
 
 #ifdef MODE_GAUSSIAN_BLUR
 
-	// Simpler blur uses SIGMA2 for the gaussian kernel for a stronger effect
-
-	// note, for blur blur.luminance_multiplier is irrelavant, we would be multiplying and then dividing by this amount.
-
-	if (bool(blur.flags & FLAG_HORIZONTAL)) {
-		vec2 pix_size = blur.pixel_size;
-		pix_size *= 0.5; //reading from larger buffer, so use more samples
-		vec4 color = texture(source_color, uv_interp + vec2(0.0, 0.0) * pix_size) * 0.214607;
-		color += texture(source_color, uv_interp + vec2(1.0, 0.0) * pix_size) * 0.189879;
-		color += texture(source_color, uv_interp + vec2(2.0, 0.0) * pix_size) * 0.131514;
-		color += texture(source_color, uv_interp + vec2(3.0, 0.0) * pix_size) * 0.071303;
-		color += texture(source_color, uv_interp + vec2(-1.0, 0.0) * pix_size) * 0.189879;
-		color += texture(source_color, uv_interp + vec2(-2.0, 0.0) * pix_size) * 0.131514;
-		color += texture(source_color, uv_interp + vec2(-3.0, 0.0) * pix_size) * 0.071303;
-		frag_color = color;
-	} else {
-		vec2 pix_size = blur.pixel_size;
-		vec4 color = texture(source_color, uv_interp + vec2(0.0, 0.0) * pix_size) * 0.38774;
-		color += texture(source_color, uv_interp + vec2(0.0, 1.0) * pix_size) * 0.24477;
-		color += texture(source_color, uv_interp + vec2(0.0, 2.0) * pix_size) * 0.06136;
-		color += texture(source_color, uv_interp + vec2(0.0, -1.0) * pix_size) * 0.24477;
-		color += texture(source_color, uv_interp + vec2(0.0, -2.0) * pix_size) * 0.06136;
-		frag_color = color;
-	}
+	// For Gaussian Blur we use 13 taps in a single pass instead of 12 taps over 2 passes.
+	// This minimizes the number of times we change framebuffers which is very important for mobile.
+	// Source: http://www.iryoku.com/next-generation-post-processing-in-call-of-duty-advanced-warfare
+	vec4 A = texture(source_color, uv_interp + blur.pixel_size * vec2(-1.0, -1.0));
+	vec4 B = texture(source_color, uv_interp + blur.pixel_size * vec2(0.0, -1.0));
+	vec4 C = texture(source_color, uv_interp + blur.pixel_size * vec2(1.0, -1.0));
+	vec4 D = texture(source_color, uv_interp + blur.pixel_size * vec2(-0.5, -0.5));
+	vec4 E = texture(source_color, uv_interp + blur.pixel_size * vec2(0.5, -0.5));
+	vec4 F = texture(source_color, uv_interp + blur.pixel_size * vec2(-1.0, 0.0));
+	vec4 G = texture(source_color, uv_interp);
+	vec4 H = texture(source_color, uv_interp + blur.pixel_size * vec2(1.0, 0.0));
+	vec4 I = texture(source_color, uv_interp + blur.pixel_size * vec2(-0.5, 0.5));
+	vec4 J = texture(source_color, uv_interp + blur.pixel_size * vec2(0.5, 0.5));
+	vec4 K = texture(source_color, uv_interp + blur.pixel_size * vec2(-1.0, 1.0));
+	vec4 L = texture(source_color, uv_interp + blur.pixel_size * vec2(0.0, 1.0));
+	vec4 M = texture(source_color, uv_interp + blur.pixel_size * vec2(1.0, 1.0));
+
+	float base_weight = 0.5 / 4.0;
+	float lesser_weight = 0.125 / 4.0;
+
+	frag_color = (D + E + I + J) * base_weight;
+	frag_color += (A + B + G + F) * lesser_weight;
+	frag_color += (B + C + H + G) * lesser_weight;
+	frag_color += (F + G + L + K) * lesser_weight;
+	frag_color += (G + H + M + L) * lesser_weight;
 #endif
 
 #ifdef MODE_GAUSSIAN_GLOW
diff --git a/servers/rendering/renderer_rd/shaders/effects/copy.glsl b/servers/rendering/renderer_rd/shaders/effects/copy.glsl
index bfe329b8ec..5cc2ed7622 100644
--- a/servers/rendering/renderer_rd/shaders/effects/copy.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/copy.glsl
@@ -194,10 +194,10 @@ void main() {
 
 		color = min(color * feedback, vec4(params.glow_luminance_cap));
 	}
-#endif
+#endif // MODE_GLOW
 	imageStore(dest_buffer, pos + params.target, color);
 
-#endif
+#endif // MODE_GAUSSIAN_BLUR
 
 #ifdef MODE_SIMPLE_COPY
 
@@ -227,7 +227,7 @@ void main() {
 
 	imageStore(dest_buffer, pos + params.target, color);
 
-#endif
+#endif // MODE_SIMPLE_COPY
 
 #ifdef MODE_SIMPLE_COPY_DEPTH
 
@@ -239,7 +239,7 @@ void main() {
 
 	imageStore(dest_buffer, pos + params.target, vec4(color.r));
 
-#endif
+#endif // MODE_SIMPLE_COPY_DEPTH
 
 #ifdef MODE_LINEARIZE_DEPTH_COPY
 
@@ -253,7 +253,7 @@ void main() {
 	}
 
 	imageStore(dest_buffer, pos + params.target, color);
-#endif
+#endif // MODE_LINEARIZE_DEPTH_COPY
 
 #if defined(MODE_CUBEMAP_TO_PANORAMA) || defined(MODE_CUBEMAP_ARRAY_TO_PANORAMA)
 
@@ -276,7 +276,7 @@ void main() {
 	vec4 color = textureLod(source_color, vec4(normal, params.camera_z_far), 0.0); //the biggest the lod the least the acne
 #endif
 	imageStore(dest_buffer, pos + params.target, color);
-#endif
+#endif // defined(MODE_CUBEMAP_TO_PANORAMA) || defined(MODE_CUBEMAP_ARRAY_TO_PANORAMA)
 
 #ifdef MODE_SET_COLOR
 	imageStore(dest_buffer, pos + params.target, params.set_color);
diff --git a/servers/rendering/renderer_rd/shaders/effects/copy_to_fb.glsl b/servers/rendering/renderer_rd/shaders/effects/copy_to_fb.glsl
index 1c17eabb56..4d4e983b7f 100644
--- a/servers/rendering/renderer_rd/shaders/effects/copy_to_fb.glsl
+++ b/servers/rendering/renderer_rd/shaders/effects/copy_to_fb.glsl
@@ -26,7 +26,11 @@ layout(push_constant, std430) uniform Params {
 	bool use_section;
 
 	bool force_luminance;
-	uint pad[3];
+	bool alpha_to_zero;
+	bool srgb;
+	bool alpha_to_one;
+
+	vec4 color;
 }
 params;
 
@@ -72,7 +76,9 @@ layout(push_constant, std430) uniform Params {
 	bool force_luminance;
 	bool alpha_to_zero;
 	bool srgb;
-	uint pad;
+	bool alpha_to_one;
+
+	vec4 color;
 }
 params;
 
@@ -105,6 +111,10 @@ vec3 linear_to_srgb(vec3 color) {
 }
 
 void main() {
+#ifdef MODE_SET_COLOR
+	frag_color = params.color;
+#else
+
 #ifdef MULTIVIEW
 	vec3 uv = uv_interp;
 #else
@@ -164,6 +174,10 @@ void main() {
 	if (params.srgb) {
 		color.rgb = linear_to_srgb(color.rgb);
 	}
+	if (params.alpha_to_one) {
+		color.a = 1.0;
+	}
 
 	frag_color = color;
+#endif // MODE_SET_COLOR
 }