!Copyright (c) 2013 by https://git.em3d.cn/ under guide of Xiu Li(lixiu@chd.edu.cn)
!written by Huaifeng Sun(sunhuaifeng@email.sdu.edu.cn) and Xushan Lu(luxushan@gmail.com)
!Code distribution @ https://git.em3d.cn/
    
SUBROUTINE GET_NON_UNIFORMGRID
  USE CONSTANTPARAMETERS
  USE OMP_LIB
  IMPLICIT NONE
  INTEGER II
  INTEGER MID_P,LEFT_P,RIGHT_P,UP_P,DOWN_P
  REAL(KIND=8) CDELX_LENGTH,CDELY_LENGTH,CDELZ_LENGTH
  WRITE(*,*)'Non-uniform grid meshing: core cells = ',GridSize,' m, expansion ratio SCALE_PAR = ',SCALE_PAR
  ! -------------------------mesh-z-------------------------------------------!
  GridSize_MAX=GridSize*MAX_RATIO
  do ii=nzs-UniGridNumZ1,nzs+UniGridNumZ2,1
     Cdelz(ii)=GridSize
  end do                        !Uniform mesh in an area equal to source length
  do ii=nzs-UniGridNumZ1-1,1,-1
     Cdelz(ii)=Cdelz(ii+1)*scale_par
     if(Cdelz(ii).gt.GridSize_MAX)then
        Cdelz(ii)=GridSize_MAX
     end if
  end do                        !Ununiform mesh in the air.
  do ii=nzs+UniGridNumZ2+1,nz,1
     Cdelz(ii)=Cdelz(ii-1)*scale_par
     if(Cdelz(ii).gt.GridSize_MAX)then
        Cdelz(ii)=GridSize_MAX
     end if
  end do                        !Ununiform mesh underground
  ! ----------------------------end of mesh------------------------------------!
  ! -------------------------------mesh x----------------------------------------!
  IF(Logi_Sourcelenth) THEN    !The number of grids occupied by the source is odd
	if(SourceLength/GridSize.gt.51)then
     do ii=nxs-(SourceLength/GridSize-1)/2,nxs+(SourceLength/GridSize-1)/2,1
        Cdelx(ii)=GridSize
     end do
     do ii=nxs-(SourceLength/GridSize-1)/2-1,1,-1
        Cdelx(ii)=Cdelx(ii+1)*scale_par
        if(Cdelx(ii).gt.GridSize_MAX)then
           Cdelx(ii)=GridSize_MAX
        end if
     end do
     do ii=nxs+(SourceLength/GridSize-1)/2+1,nx,1
        Cdelx(ii)=Cdelx(ii-1)*scale_par
        if(Cdelx(ii).gt.GridSize_MAX)then
           Cdelx(ii)=GridSize_MAX
        end if
     end do
	else
     do ii=nxs-UniGridNumX1,nxs+UniGridNumX2,1
        Cdelx(ii)=GridSize
     end do
     do ii=nxs-UniGridNumX1-1,1,-1
        Cdelx(ii)=Cdelx(ii+1)*scale_par
        if(Cdelx(ii).gt.GridSize_MAX)then
           Cdelx(ii)=GridSize_MAX
        end if
     end do
     do ii=nxs+UniGridNumX2+1,nx,1
        Cdelx(ii)=Cdelx(ii-1)*scale_par
        if(Cdelx(ii).gt.GridSize_MAX)then
           Cdelx(ii)=GridSize_MAX
        endif
     end do
	ENDIF
  ELSE    !The number of grids occupied by the source is even
	if(SourceLength/GridSize.gt.51)then
		do ii=nxs-(SourceLength/GridSize-1)/2,nxs+1+(SourceLength/GridSize-1)/2,1
			Cdelx(ii)=GridSize
		end do
		do ii=nxs-(SourceLength/GridSize-1)/2-1,1,-1
			Cdelx(ii)=Cdelx(ii+1)*scale_par
			if(Cdelx(ii).gt.GridSize_MAX)then
				Cdelx(ii)=GridSize_MAX
			end if
		end do
		do ii=nxs+(SourceLength/GridSize-1)/2+2,nx,1
			Cdelx(ii)=Cdelx(ii-1)*scale_par
			if(Cdelx(ii).gt.GridSize_MAX)then
				Cdelx(ii)=GridSize_MAX
			end if
		end do
	else
		do ii=nxs-UniGridNumX1-1,nxs+UniGridNumX2,1
			Cdelx(ii)=GridSize
		end do
		do ii=nxs-UniGridNumX1,1,-1
			Cdelx(ii)=Cdelx(ii+1)*scale_par
			if(Cdelx(ii).gt.GridSize_MAX)then
				Cdelx(ii)=GridSize_MAX
			end if
		end do
		do ii=nxs+UniGridNumX2+1,nx,1
			Cdelx(ii)=Cdelx(ii-1)*scale_par
			if(Cdelx(ii).gt.GridSize_MAX)then
				Cdelx(ii)=GridSize_MAX
			endif
		end do
	ENDIF
  ENDIF
  ! -----------------------------end of mesh------------------------------------!
  ! --------------------------------mesh y----------------------------------------!
  IF(Logi_Sourcelenth) THEN    !The number of grids occupied by the source is odd
	IF(SourceLength/GridSize.gt.51)then
		do ii=nys-(SourceLength/GridSize-1)/2,nys+(SourceLength/GridSize-1)/2,1
			Cdely(ii)=GridSize
		enddo
		do ii=nys-(SourceLength/GridSize-1)/2-1,1,-1
			Cdely(ii)=Cdely(ii+1)*scale_par
			if(Cdely(ii).gt.GridSize_MAX)then
				Cdely(ii)=GridSize_MAX
			end if
		end do
		do ii=nys+(SourceLength/GridSize-1)/2+1,ny,1
			Cdely(ii)=Cdely(ii-1)*scale_par
			if(Cdely(ii).gt.GridSize_MAX)then
				Cdely(ii)=GridSize_MAX
			endif
		end do
	else 
		do ii=nys-UniGridNumY1,nys+UniGridNumY2,1
			Cdely(ii)=GridSize
		end do
		do ii=nys-UniGridNumY1-1,1,-1
			Cdely(ii)=Cdely(ii+1)*scale_par
			if(Cdely(ii).gt.GridSize_MAX)then
				Cdely(ii)=GridSize_MAX
			end if
		end do
		do ii=nys+UniGridNumY2+1,ny,1
			Cdely(ii)=Cdely(ii-1)*scale_par
			if(Cdely(ii).gt.GridSize_MAX)then
				Cdely(ii)=GridSize_MAX
			end if
		end do
	end if
  ELSE	!The number of grids occupied by the source is even
	IF(SourceLength/GridSize.gt.51)then
		do ii=nys-(SourceLength/GridSize-1)/2,nys+1+(SourceLength/GridSize-1)/2,1
			Cdely(ii)=GridSize
		enddo
		do ii=nys-(SourceLength/GridSize-1)/2-1,1,-1
			Cdely(ii)=Cdely(ii+1)*scale_par
			if(Cdely(ii).gt.GridSize_MAX)then
				Cdely(ii)=GridSize_MAX
			end if
		end do
		do ii=nys+(SourceLength/GridSize-1)/2+2,ny,1
			Cdely(ii)=Cdely(ii-1)*scale_par
			if(Cdely(ii).gt.GridSize_MAX)then
				Cdely(ii)=GridSize_MAX
			endif
		end do
	else 
		do ii=nys-UniGridNumY1-1,nys+UniGridNumY2,1
			Cdely(ii)=GridSize
		end do
		do ii=nys-UniGridNumY1,1,-1
			Cdely(ii)=Cdely(ii+1)*scale_par
			if(Cdely(ii).gt.GridSize_MAX)then
				Cdely(ii)=GridSize_MAX
			end if
		end do
		do ii=nys+UniGridNumY2+1,ny,1
			Cdely(ii)=Cdely(ii-1)*scale_par
			if(Cdely(ii).gt.GridSize_MAX)then
				Cdely(ii)=GridSize_MAX
			end if
		end do
	end if
  ENDIF
  ! ------------------------------end of mesh-----------------------------------!

  CDELX_LENGTH=SUM(CDELX)
  CDELY_LENGTH=SUM(CDELY)
  CDELZ_LENGTH=SUM(CDELZ)
  WRITE(10005,*)'���õ�ģ�ͳߴ�Ϊ��'
  WRITE(10005,*)'SUM_X=',CDELX_LENGTH
  WRITE(10005,*)'SUM_Y=',CDELY_LENGTH
  WRITE(10005,*)'SUM_Z=',CDELZ_LENGTH

  WRITE(10005,*)'��������Ŵ�ϵ��=',SCALE_PAR
  WRITE(10005,*)'�������ߴ�����С����ߴ�֮��<=',MAX_RATIO
  WRITE(10005,*)'X����ķǾ�������ߴ�Ϊ��'
  WRITE(10005,'(5F18.8)')CDELX

  WRITE(10005,*)'Y����ķǾ�������ߴ�Ϊ��'
  WRITE(10005,'(5F18.8)')CDELY
  WRITE(10005,*)'Z����ķǾ�������ߴ�Ϊ��'
  WRITE(10005,'(5F18.8)')CDELZ

  WRITE(*,*)'Model size:',CDELX_LENGTH,CDELY_LENGTH,CDELZ_LENGTH
ENDSUBROUTINE GET_NON_UNIFORMGRID

!===============================================================================================!
!  GET_UNIFORM_GRID: 均匀网格剖分，用于 CPML 吸收边界。
!  参考实现（tem3dfdtd_第二版）中 CPML 采用的是均匀网格（SCALE_PAR=1.0，
!  扩展循环全部注释），因此这里按 Logic_PML 分流：Logic_PML=1 时调用本子程序
!  （均匀网格 + CPML），Logic_PML=0 时调用 GET_NON_UNIFORMGRID（非均匀网格 + Dirichlet）。
!===============================================================================================!
SUBROUTINE GET_UNIFORM_GRID
  USE CONSTANTPARAMETERS
  IMPLICIT NONE
  INTEGER II
  REAL(KIND=8) CDELX_LENGTH,CDELY_LENGTH,CDELZ_LENGTH
  WRITE(*,*)'Uniform grid meshing: all cells = ',GridSize,' m (required by the CPML absorbing boundary)'
  ! 均匀网格：所有网格尺寸均等于 GridSize
  Cdelx=GridSize
  Cdely=GridSize
  Cdelz=GridSize

  CDELX_LENGTH=SUM(CDELX)
  CDELY_LENGTH=SUM(CDELY)
  CDELZ_LENGTH=SUM(CDELZ)
  WRITE(10005,*)'采用均匀网格剖分（配合 CPML 吸收边界）:'
  WRITE(10005,*)'SUM_X=',CDELX_LENGTH
  WRITE(10005,*)'SUM_Y=',CDELY_LENGTH
  WRITE(10005,*)'SUM_Z=',CDELZ_LENGTH
  WRITE(10005,*)'均匀网格尺寸=',GridSize

  WRITE(*,*)'Model size:',CDELX_LENGTH,CDELY_LENGTH,CDELZ_LENGTH

  OPEN(400,FILE='CDELX.DAT',STATUS='UNKNOWN')
  DO II=1,NX
     WRITE(400,'(E13.6)')CDELX(II)
  ENDDO
  CLOSE(400)
  OPEN(400,FILE='CDELY.DAT',STATUS='UNKNOWN')
  DO II=1,NY
     WRITE(400,'(E13.6)')CDELY(II)
  ENDDO
  CLOSE(400)
  OPEN(400,FILE='CDELZ.DAT',STATUS='UNKNOWN')
  DO II=1,NZ
     WRITE(400,'(E13.6)')CDELZ(II)
  ENDDO
  CLOSE(400)
ENDSUBROUTINE GET_UNIFORM_GRID