add String method (#552)

* all: add String() method for improved log output

core_string.go

@@ -0,0 +1,211 @@
+package gocv
+
+func (c MatType) String() string {
+	switch c {
+	case MatTypeCV8U:
+		return "CV8U"
+	case MatTypeCV8UC2:
+		return "CV8UC2"
+	case MatTypeCV8UC3:
+		return "CV8UC3"
+	case MatTypeCV8UC4:
+		return "CV8UC4"
+	case MatTypeCV16U:
+		return "CV16U"
+	case MatTypeCV16UC2:
+		return "CV16UC2"
+	case MatTypeCV16UC3:
+		return "CV16UC3"
+	case MatTypeCV16UC4:
+		return "CV16UC4"
+	case MatTypeCV16S:
+		return "CV16S"
+	case MatTypeCV16SC2:
+		return "CV16SC2"
+	case MatTypeCV16SC3:
+		return "CV16SC3"
+	case MatTypeCV16SC4:
+		return "CV16SC4"
+	case MatTypeCV32S:
+		return "CV32S"
+	case MatTypeCV32SC2:
+		return "CV32SC2"
+	case MatTypeCV32SC3:
+		return "CV32SC3"
+	case MatTypeCV32SC4:
+		return "CV32SC4"
+	case MatTypeCV32F:
+		return "CV32F"
+	case MatTypeCV32FC2:
+		return "CV32FC2"
+	case MatTypeCV32FC3:
+		return "CV32FC3"
+	case MatTypeCV32FC4:
+		return "CV32FC4"
+	case MatTypeCV64F:
+		return "CV64F"
+	case MatTypeCV64FC2:
+		return "CV64FC2"
+	case MatTypeCV64FC3:
+		return "CV64FC3"
+	case MatTypeCV64FC4:
+		return "CV64FC4"
+	}
+	return ""
+}
+
+func (c CompareType) String() string {
+	switch c {
+	case CompareEQ:
+		return "eq"
+	case CompareGT:
+		return "gt"
+	case CompareGE:
+		return "ge"
+	case CompareLT:
+		return "lt"
+	case CompareLE:
+		return "le"
+	case CompareNE:
+		return "ne"
+	}
+	return ""
+}
+
+func (c CovarFlags) String() string {
+	switch c {
+	case CovarScrambled:
+		return "covar-scrambled"
+	case CovarNormal:
+		return "covar-normal"
+	case CovarUseAvg:
+		return "covar-use-avg"
+	case CovarScale:
+		return "covar-scale"
+	case CovarRows:
+		return "covar-rows"
+	case CovarCols:
+		return "covar-cols"
+	}
+	return ""
+}
+
+func (c DftFlags) String() string {
+	switch c {
+	case DftForward:
+		return "dft-forward"
+	case DftInverse:
+		return "dft-inverse"
+	case DftScale:
+		return "dft-scale"
+	case DftRows:
+		return "dft-rows"
+	case DftComplexOutput:
+		return "dft-complex-output"
+	case DftRealOutput:
+		return "dft-real-output"
+	case DftComplexInput:
+		return "dft-complex-input"
+	}
+	return ""
+}
+
+func (c RotateFlag) String() string {
+	switch c {
+	case Rotate90Clockwise:
+		return "rotate-90-clockwise"
+	case Rotate180Clockwise:
+		return "rotate-180-clockwise"
+	case Rotate90CounterClockwise:
+		return "rotate-90-counter-clockwise"
+	}
+	return ""
+}
+
+func (c KMeansFlags) String() string {
+	switch c {
+	case KMeansRandomCenters:
+		return "kmeans-random-centers"
+	case KMeansPPCenters:
+		return "kmeans-pp-centers"
+	case KMeansUseInitialLabels:
+		return "kmeans-use-initial-labels"
+	}
+	return ""
+}
+
+func (c NormType) String() string {
+	switch c {
+	case NormInf:
+		return "norm-inf"
+	case NormL1:
+		return "norm-l1"
+	case NormL2:
+		return "norm-l2"
+	case NormL2Sqr:
+		return "norm-l2-sqr"
+	case NormHamming:
+		return "norm-hamming"
+	case NormHamming2:
+		return "norm-hamming2"
+	case NormRelative:
+		return "norm-relative"
+	case NormMinMax:
+		return "norm-minmax"
+	}
+	return ""
+}
+
+func (c TermCriteriaType) String() string {
+	switch c {
+	case Count:
+		return "count"
+	case EPS:
+		return "eps"
+	}
+	return ""
+}
+
+func (c SolveDecompositionFlags) String() string {
+	switch c {
+	case SolveDecompositionLu:
+		return "solve-decomposition-lu"
+	case SolveDecompositionSvd:
+		return "solve-decomposition-svd"
+	case SolveDecompositionEing:
+		return "solve-decomposition-eing"
+	case SolveDecompositionCholesky:
+		return "solve-decomposition-cholesky"
+	case SolveDecompositionQr:
+		return "solve-decomposition-qr"
+	case SolveDecompositionNormal:
+		return "solve-decomposition-normal"
+	}
+	return ""
+}
+
+func (c ReduceTypes) String() string {
+	switch c {
+	case ReduceSum:
+		return "reduce-sum"
+	case ReduceAvg:
+		return "reduce-avg"
+	case ReduceMax:
+		return "reduce-max"
+	case ReduceMin:
+		return "reduce-min"
+	}
+	return ""
+}
+
+func (c SortFlags) String() string {
+	switch c {
+	case SortEveryRow:
+		return "sort-every-row"
+	case SortEveryColumn:
+		return "sort-every-column"
+	case SortDescending:
+		return "sort-descending"
+	}
+	return ""
+}