R/readCam.R

In aaronolsen/svgViewR: 3D Animated Interactive Visualizations Using SVG and WebGL

readCam <- function(file, scale=1){

	# If file is already camera just return file
	if(inherits(file, 'camera')) return(file)
	
	## Reads MayaCam file exported from XMALab
	read_lines <- readLines(file)
	
	image_size <- as.numeric(strsplit(read_lines[2], ',')[[1]])

	intrinsic <- matrix(NA, 3, 3)
	intrinsic[1,] <- as.numeric(strsplit(read_lines[5], ',')[[1]])
	intrinsic[2,] <- as.numeric(strsplit(read_lines[6], ',')[[1]])
	intrinsic[3,] <- as.numeric(strsplit(read_lines[7], ',')[[1]])

	extrinsic <- matrix(NA, 3, 4)
	extrinsic[1,1:3] <- as.numeric(strsplit(read_lines[10], ',')[[1]])
	extrinsic[2,1:3] <- as.numeric(strsplit(read_lines[11], ',')[[1]])
	extrinsic[3,1:3] <- as.numeric(strsplit(read_lines[12], ',')[[1]])
	extrinsic[,4] <- as.numeric(read_lines[15:17])*scale

	# Calculate camera parameters
	cam_params <- cameraParameters(intrinsic, extrinsic, image_size)

	camera <- list(
		'image.size'=image_size,
		'intrinsic'=intrinsic,
		'extrinsic'=extrinsic,
		'pinhole'=cam_params$pinhole,
		'plane.corners'=cam_params$plane.corners,
		'plane.dist'=cam_params$plane.dist,
		'prin.uvec'=cam_params$prin.uvec,
		'prin.vec'=cam_params$prin.vec,
		'prin.axis'=cam_params$prin.axis
	)
	
	class(camera) <- 'camera'
	
	camera
}