Merge pull request #53976 from nicbn/something-refactor

Makes cameras process transforms instead of reading mob angles

code/__HELPERS/matrices.dm

@@ -1,3 +1,36 @@
+/// Datum which stores information about a matrix decomposed with decompose().
+/datum/decompose_matrix
+	///?
+	var/scale_x = 1
+	///?
+	var/scale_y = 1
+	///?
+	var/rotation = 0
+	///?
+	var/shift_x = 0
+	///?
+	var/shift_y = 0
+
+/// Decomposes a matrix into scale, shift and rotation.
+///
+/// If other operations were applied on the matrix, such as shearing, the result
+/// will not be precise.
+///
+/// Negative scales are not supported.
+/matrix/proc/decompose()
+	var/datum/decompose_matrix/decompose_matrix = new
+	. = decompose_matrix
+	decompose_matrix.scale_x = sqrt(a * a + d * d)
+	decompose_matrix.scale_y = sqrt(b * b + e * e)
+	decompose_matrix.shift_x = c
+	decompose_matrix.shift_y = f
+	if(!decompose_matrix.scale_x || !decompose_matrix.scale_y)
+		return
+	// If only translated, scaled and rotated, a/xs == e/ys and -d/xs == b/xy
+	var/cossine = (a/decompose_matrix.scale_x + e/decompose_matrix.scale_y) / 2
+	var/sine = (b/decompose_matrix.scale_y - d/decompose_matrix.scale_x) / 2
+	decompose_matrix.rotation = arctan(cossine, sine)
+
 /matrix/proc/TurnTo(old_angle, new_angle)
 	. = new_angle - old_angle
 	Turn(.) //BYOND handles cases such as -270, 360, 540 etc. DOES NOT HANDLE 180 TURNS WELL, THEY TWEEN AND LOOK LIKE SHIT
@@ -55,30 +88,14 @@
 	. += f
 	. += 1
 
-//The X pixel offset of this matrix
+///The X pixel offset of this matrix
 /matrix/proc/get_x_shift()
 	. = c
 
-//The Y pixel offset of this matrix
+///The Y pixel offset of this matrix
 /matrix/proc/get_y_shift()
 	. = f
 
-/matrix/proc/get_x_skew()
-	. = b
-
-/matrix/proc/get_y_skew()
-	. = d
-
-//Skews a matrix in a particular direction
-//Missing arguments are treated as no skew in that direction
-
-//As Rotation is defined as a scale+skew, these procs will break any existing rotation
-//Unless the result is multiplied against the current matrix
-/matrix/proc/set_skew(x = 0, y = 0)
-	b = x
-	d = y
-
-
 /////////////////////
 // COLOUR MATRICES //
 /////////////////////

code/modules/photography/camera/camera_image_capturing.dm

@@ -1,5 +1,4 @@
 /obj/effect/appearance_clone
-	var/turn_angle = 0
 
 /obj/effect/appearance_clone/New(loc, atom/A)			//Intentionally not Initialize(), to make sure the clone assumes the intended appearance in time for the camera getFlatIcon.
 	if(istype(A))
@@ -9,9 +8,6 @@
 			var/atom/movable/AM = A
 			step_x = AM.step_x
 			step_y = AM.step_y
-			if(iscarbon(A))
-				var/mob/living/carbon/C = A
-				UNLINT(turn_angle = C.lying_angle) // this is the only place its okay to read lying directly
 	. = ..()
 
 /obj/item/camera/proc/camera_get_icon(list/turfs, turf/center, psize_x = 96, psize_y = 96, datum/turf_reservation/clone_area, size_x, size_y, total_x, total_y)
@@ -82,14 +78,29 @@
 	else
 		for(var/X in sorted) //these are clones
 			var/obj/effect/appearance_clone/clone = X
-			var/xo = (clone.x - center.x) * world.icon_size + clone.pixel_x + xcomp
-			var/yo = (clone.y - center.y) * world.icon_size + clone.pixel_y + ycomp
-			xo += clone.step_x
-			yo += clone.step_y
 			var/icon/img = getFlatIcon(clone, no_anim = TRUE)
 			if(img)
-				if(clone.turn_angle) //the cheapest (so best, considering cams don't need to be laggier) way of doing this, considering getFlatIcon doesn't give a snot about transforms.'
-					img.Turn(clone.turn_angle)
+				// Center of the image in X
+				var/xo = (clone.x - center.x) * world.icon_size + clone.pixel_x + xcomp + clone.step_x
+				// Center of the image in Y
+				var/yo = (clone.y - center.y) * world.icon_size + clone.pixel_y + ycomp + clone.step_y
+
+				if(clone.transform) // getFlatIcon doesn't give a snot about transforms.
+					var/datum/decompose_matrix/decompose = clone.transform.decompose()
+					// Scale in X, Y
+					if(decompose.scale_x != 1 || decompose.scale_y != 1)
+						var/base_w = img.Width()
+						var/base_h = img.Height()
+						img.Scale(base_w * decompose.scale_x, base_h * decompose.scale_y)
+						xo -= base_w * (decompose.scale_x - 1) / 2
+						yo -= base_h * (decompose.scale_y - 1) / 2
+					// Rotation
+					if(decompose.rotation != 0)
+						img.Turn(decompose.rotation)
+					// Shift
+					xo += decompose.shift_x
+					yo += decompose.shift_y
+
 				res.Blend(img, blendMode2iconMode(clone.blend_mode), xo, yo)
 			CHECK_TICK