fortran-sdl2 package

Our fortran-sdl2 package is a bit old.  I'll try to get an update posted soon.

I've updated fortran-sdl2 to the lastest repo version, and it seems to be working fine.  It is using the latest SDL2 packages as well. 

One word of warning: the Fortran library name has changed, which could cause an existing project's linking step to fail.  The library flag is now:

-lfortran-sdl2

Let me know if there's any problem!

Interesting, I didn't see this issue.  Did you also reinstall:

- Simple DirectMedia Layer
- SDL2_image
- SDL2_mixer
- SDL2_ttf

I'm not sure it would upgrade those automatically. 

You say you've "uninstalled and reinstalled opengl," but I'm not sure I understand what package you're talking about.  glclearcolor is available in the sdl2 module, and it doesn't require any other imports.  I'm not sure if you're calling it directly or not.

sdl_create_rgb_surface_from does seem to be bound.  Are you using the correct function call?

dear Jeff,
Happy New year!
I seem to have the correct function calls: "sdl_create_rgb_surface_from" and "sdl_save_bmp".
The library flag reads "lfortran-sdl2".
However I still get undefined references. I hope you can help. A part of the *build status* looks like this:

==============================================================================
Generating Makefile... Okay
==============================================================================
Processing default resource
Generating atb_ex.dll.exe
C:/Users/csitt/AppData/Local/sfpm/64/lib\libfortran-sdl2.a(sdl2.o): In function `__sdl2_MOD_sdl_log_warn':
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
C:\Users\jeffr\Workspace\packages\fortran_sdl2\fortran-sdl2/src/sdl2.f90:587: undefined reference to `SDL_LogWarn'
C:/Users/csitt/AppData/Local/sfpm/64/lib\libfortran-sdl2.a(sdl2.o): In function `__sdl2_MOD_sdl_log_verbose':
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
C:\Users\jeffr\Workspace\packages\fortran_sdl2\fortran-sdl2/src/sdl2.f90:578: undefined reference to `SDL_LogVerbose'
C:/Users/csitt/AppData/Local/sfpm/64/lib\libfortran-sdl2.a(sdl2.o): In function `__sdl2_MOD_sdl_log_info':
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
C:\Users\jeffr\Workspace\packages\fortran_sdl2\fortran-sdl2/src/sdl2.f90:569: undefined reference to `SDL_LogInfo'
C:/Users/csitt/AppData/Local/sfpm/64/lib\libfortran-sdl2.a(sdl2.o): In function `__sdl2_MOD_sdl_log_error':
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
C:\Users\jeffr\Workspace\packages\fortran_sdl2\fortran-sdl2/src/sdl2.f90:560: undefined reference to `SDL_LogError'
C:/Users/csitt/AppData/Local/sfpm/64/lib\libfortran-sdl2.a(sdl2.o): In function `__sdl2_MOD_sdl_log_debug':

As you probably are aware I am new to opengl and sld2
I managed to compile the software without errors.
when I run the programme it creates a bmp file, but it is empty.
I tried several things, but am not able to solve the problem.
I try to save a window of 750x500 pixels (iwidth x iheight) containing an 2D image of a FEM boundary with basepoints and numbering.

the routine that should do the job reads:

subroutine save_image2()

use opengl_glu
use opengl_glut
use common_window
use, intrinsic :: iso_fortran_env, only: i1 => int8, i8 => int64, r8 => real64,&
                  stderr => error_unit, stdout => output_unit
use :: sdl2
use :: sdl2_image
use :: SDL2_mixer
use :: SDL2_ttf
   
implicit none
type(c_ptr),dimension(0:iwidth*iheight*3) :: image
type(sdl_surface),pointer :: bitmap
integer :: idepth,ipitch,mm

call glReadPixels(0,0,iwidth,iheight,GL_RGB,GL_UNSIGNED_BYTE,image)
idepth=32
ipitch=4*iwidth
!ipitch=0
bitmap => SDL_Create_RGB_Surface_From(image,iwidth,iheight,idepth,ipitch,&
         int(z'000000ff',kind=i8),int(z'0000ff00',kind=i8),&
         int(z'00ff0000',kind=i8),int(z'ff000000',kind=i8))
mm=sdl_save_bmp(bitmap,"test.bmp")

endsubroutine save_image2

If I fill out ipitch = 0, I get the empty bmp file
if I fill out ipitch = 4*iwidth I get an error (see below)

At line 28 of file .\save_image2.f90
Fortran runtime error: Pointer actual argument 'bitmap' is not associated
Error termination.

The window sizes iwidth and iheight are obtained via the common block "common_window"

I hope I provided enough information

I adapted the code, it looks as follows:

subroutine save_image2()

use opengl_glu
use opengl_glut
use common_window
use, intrinsic :: iso_fortran_env, only: i1 => int8, i8 => int64, r8 => real64,&
                  stderr => error_unit, stdout => output_unit
use :: sdl2
use :: sdl2_image
use :: SDL2_mixer
use :: SDL2_ttf
   
implicit none
integer(kind=GLbyte), dimension(:), pointer::image
type(sdl_surface),pointer :: bitmap
integer :: idepth,ipitch,mm
allocate(image(iwidth*iheight*4))  ! assumes 4 bytes (RGB + alpha per pixel)

call glReadPixels(0,0,iwidth,iheight,GL_RGBA,GL_UNSIGNED_BYTE,c_loc(image))
idepth=32
ipitch=4*iwidth
!ipitch=0
bitmap => SDL_Create_RGB_Surface_From(c_loc(image),iwidth,iheight,idepth,&
   ipitch, int(z'000000ff',kind=i8),int(z'0000ff00',kind=i8),&
           int(z'00ff0000',kind=i8),int(z'ff000000',kind=i8))
       
mm=sdl_save_bmp(bitmap,"test.bmp")

endsubroutine save_image2

However I still get the same error:
At line 27 of file .\save_image2.f90
Fortran runtime error: Pointer actual argument 'bitmap' is not associated
Error termination.

Can it be that bitmap is a "sdl_surface pointer" and sdl_save_bmp requires a "sdl_surface"??

If I fill out ipitch=0 the code runs, but the saved file is empty

The version in the SF Package Manager has been updated to correct the issue.  Hopefully your code works now.