Merge pull request #63589 from RandomShaper/sdfgi_debug_pc

Keep SdfgiDebug shader's push constant size <= 128

3 files changed, 28 insertions, 35 deletions

diff --git a/servers/rendering/renderer_rd/environment/gi.cpp b/servers/rendering/renderer_rd/environment/gi.cpp
index 7cda0337b8..feafcc42c9 100644
--- a/servers/rendering/renderer_rd/environment/gi.cpp
+++ b/servers/rendering/renderer_rd/environment/gi.cpp
@@ -1591,34 +1591,24 @@ void GI::SDFGI::debug_draw(uint32_t p_view_count, const Projection *p_projection
 		push_constant.max_cascades = cascades.size();
 		push_constant.screen_size[0] = p_width;
 		push_constant.screen_size[1] = p_height;
-		push_constant.probe_axis_size = probe_axis_count;
-		push_constant.use_occlusion = uses_occlusion;
 		push_constant.y_mult = y_mult;
 
 		push_constant.z_near = -p_projections[v].get_z_near();
 
-		push_constant.cam_transform[0] = p_transform.basis.rows[0][0];
-		push_constant.cam_transform[1] = p_transform.basis.rows[1][0];
-		push_constant.cam_transform[2] = p_transform.basis.rows[2][0];
-		push_constant.cam_transform[3] = 0;
-		push_constant.cam_transform[4] = p_transform.basis.rows[0][1];
-		push_constant.cam_transform[5] = p_transform.basis.rows[1][1];
-		push_constant.cam_transform[6] = p_transform.basis.rows[2][1];
-		push_constant.cam_transform[7] = 0;
-		push_constant.cam_transform[8] = p_transform.basis.rows[0][2];
-		push_constant.cam_transform[9] = p_transform.basis.rows[1][2];
-		push_constant.cam_transform[10] = p_transform.basis.rows[2][2];
-		push_constant.cam_transform[11] = 0;
-		push_constant.cam_transform[12] = p_transform.origin.x;
-		push_constant.cam_transform[13] = p_transform.origin.y;
-		push_constant.cam_transform[14] = p_transform.origin.z;
-		push_constant.cam_transform[15] = 1;
+		for (int i = 0; i < 3; i++) {
+			for (int j = 0; j < 3; j++) {
+				push_constant.cam_basis[i][j] = p_transform.basis.rows[j][i];
+			}
+		}
+		push_constant.cam_origin[0] = p_transform.origin[0];
+		push_constant.cam_origin[1] = p_transform.origin[1];
+		push_constant.cam_origin[2] = p_transform.origin[2];
 
 		// need to properly unproject for asymmetric projection matrices in stereo..
 		Projection inv_projection = p_projections[v].inverse();
 		for (int i = 0; i < 4; i++) {
-			for (int j = 0; j < 4; j++) {
-				push_constant.inv_projection[i * 4 + j] = inv_projection.matrix[i][j];
+			for (int j = 0; j < 3; j++) {
+				push_constant.inv_projection[j][i] = inv_projection.matrix[i][j];
 			}
 		}
 
diff --git a/servers/rendering/renderer_rd/environment/gi.h b/servers/rendering/renderer_rd/environment/gi.h
index d4d4182950..304df1605b 100644
--- a/servers/rendering/renderer_rd/environment/gi.h
+++ b/servers/rendering/renderer_rd/environment/gi.h
@@ -232,16 +232,13 @@ private:
 			uint32_t max_cascades;
 
 			int32_t screen_size[2];
-			uint32_t use_occlusion;
 			float y_mult;
 
-			uint32_t probe_axis_size;
 			float z_near;
-			float reserved1;
-			float reserved2;
 
-			float cam_transform[16];
-			float inv_projection[16];
+			float inv_projection[3][4];
+			float cam_basis[3][3];
+			float cam_origin[3];
 		};
 
 		SdfgiDebugShaderRD debug;
diff --git a/servers/rendering/renderer_rd/shaders/environment/sdfgi_debug.glsl b/servers/rendering/renderer_rd/shaders/environment/sdfgi_debug.glsl
index af5f7d0a58..9640d30e78 100644
--- a/servers/rendering/renderer_rd/shaders/environment/sdfgi_debug.glsl
+++ b/servers/rendering/renderer_rd/shaders/environment/sdfgi_debug.glsl
@@ -37,16 +37,14 @@ layout(push_constant, std430) uniform Params {
 	uint max_cascades;
 
 	ivec2 screen_size;
-	bool use_occlusion;
 	float y_mult;
 
-	int probe_axis_size;
 	float z_near;
-	float reserved1;
-	float reserved2;
 
-	mat4 cam_transform;
-	mat4 inv_projection;
+	mat3x4 inv_projection;
+	// We pack these more tightly than mat3 and vec3, which will require some reconstruction trickery.
+	float cam_basis[3][3];
+	float cam_origin[3];
 }
 params;
 
@@ -82,13 +80,21 @@ void main() {
 	vec3 ray_pos;
 	vec3 ray_dir;
 	{
-		ray_pos = params.cam_transform[3].xyz;
+		ray_pos = vec3(params.cam_origin[0], params.cam_origin[1], params.cam_origin[2]);
 
 		ray_dir.xy = ((vec2(screen_pos) / vec2(params.screen_size)) * 2.0 - 1.0);
 		ray_dir.z = params.z_near;
-		ray_dir = (params.inv_projection * vec4(ray_dir, 1.0)).xyz;
 
-		ray_dir = normalize(mat3(params.cam_transform) * ray_dir);
+		ray_dir = (vec4(ray_dir, 1.0) * mat4(params.inv_projection)).xyz;
+
+		mat3 cam_basis;
+		{
+			vec3 c0 = vec3(params.cam_basis[0][0], params.cam_basis[0][1], params.cam_basis[0][2]);
+			vec3 c1 = vec3(params.cam_basis[1][0], params.cam_basis[1][1], params.cam_basis[1][2]);
+			vec3 c2 = vec3(params.cam_basis[2][0], params.cam_basis[2][1], params.cam_basis[2][2]);
+			cam_basis = mat3(c0, c1, c2);
+		}
+		ray_dir = normalize(cam_basis * ray_dir);
 	}
 
 	ray_pos.y *= params.y_mult;