Recent Posts

1

General Jo Engine Help / 50Hz / 60Hz detection?

« Last post by FranMatsusaka on March 22, 2022, 10:35:34 am »

It is possible to dectect if the consol is running at 60Hz (NTSC) or 50Hz (PAL)?

Thanks in advance

2

General Jo Engine Help / Re: Can't load 8-bit image for infinite map

« Last post by FranMatsusaka on March 22, 2022, 10:33:59 am »

Sorry for the late response. Sadly I tried GIMP2 but no luck.

I found a web conversor that keeps the color deep in the result TGA file. I have not tried directly in the project but the header looked right to me.
https://www.aconvert.com/image/png-to-tga/

Good luck!

3

General Jo Engine Help / Re: Can't load 8-bit image for infinite map

« Last post by D3nX on March 03, 2022, 08:16:44 pm »

Hello, sorry for the late answer!

Thank you for taking the time to fix the issue and answer us, the picture now finally loads into the game! But yeah I think the problem come from the exportation of it. However, is there a way to export it the same way you did but with another software than photoshop? (free software such as ffmpeg, paint.net, etc...) I could not find a way to do so.

Thank you again

4

General Jo Engine Help / Re: Can't load 8-bit image for infinite map

« Last post by FranMatsusaka on February 26, 2022, 07:34:47 pm »

Hi,

I tried to use your image in the "demo - vdp2 plane" and it works nicely.


Maybe you were not exporting the TGA correctly... To make sure the TGA is in a proper format open it with a hexadecimal viewer and check if the first 16 bytes are like in this image


And here's the image exported by me if you need.
https://drive.google.com/file/d/1OL8jkjLTVjZOZIuCTjkj05hAhcMQg2C_/view?usp=sharing
I've just saved the png as 8-bit image in Photoshop (using "Save for Web & devices..." option), open the new 8bit image and save as TGA.

Good luck with your project!

5

General Jo Engine Help / Can't load 8-bit image for infinite map

« Last post by D3nX on February 25, 2022, 02:46:09 pm »

Hello !

We are a bunch of student at Epitech (Superior school for programming) and we are trying to make a Sega Saturn game as a project for our year there. However it turns out that we have some little issues :

We are trying to do a "Mode 7" like map, but when we load the texture using "jo_tga_8bits_loader", this happens :


We loaded this picture:


We also tried to convert the TGA through 8-bit using ffmpeg, image magick, without success. Can somebody help us ?

Thanks in advance

6

General Jo Engine Help / Re: TGA 8-bit in background

« Last post by FranMatsusaka on January 23, 2022, 06:50:03 pm »

I was able to "fix" it by making few changes in the library. It seems it was storing cells/tiles and map indexes horizontally. I don't know if this was done like this because of mode7 plane . If anybody want's to load 8bit tgas in the background, you will need to make small hacks/changes in __jo_create_map and jo_img_to_vdp2_cells in vdp2.c

Though, this could potentially break something else...

Code: [Select]

void                            jo_img_to_vdp2_cells(const jo_img_8bits * const img, const bool vertical_flip, unsigned char *cell)
{
    register int                x;
    register int                y;
    register int                cell_x;
    register int                cell_y;
    register int                line_y;
    register int                i;


#ifdef JO_DEBUG
        if (img == JO_NULL)
        {
            jo_core_error("img is null");
            return ;
        }
        if (JO_MOD_POW2(img->width, 8) != 0)
        {
            jo_core_error("Image width must be multiple of 8");
            return ;
        }
        if (JO_MOD_POW2(img->height, 8) != 0)
        {
            jo_core_error("Image height must be multiple of 8");
            return ;
        }
#endif

    for (JO_ZERO(y), JO_ZERO(line_y); y < img->height; y += CELL_HEIGHT, line_y += JO_MULT_BY_8(img->width))
    {
        for (JO_ZERO(x); x < img->width; x += CELL_WIDTH)
        {
            cell_x = x;
            cell_y = line_y;
            for (JO_ZERO(i); i < CELL_SIZE; ++i, ++cell, ++cell_x)
            {
                if (i != 0 && JO_MOD_POW2(i, CELL_WIDTH) == 0)
                {
                    cell_x -= CELL_WIDTH;
                    cell_y += img->width;
                }
                /**/
                if (vertical_flip)
                    *cell = img->data[(img->width - cell_x - 1) + cell_y];
                else
                 /**/
                    *cell = img->data[cell_x + cell_y];
            }
        }
    }
}

static void                     __jo_create_map(const jo_img_8bits * const img, unsigned short *map, const unsigned short palette_id, const int map_offset)
{
    register int                x;
    register int                y;
    register int                x2;
    register int                y2;
    register int                i;
    unsigned short              paloff;

    paloff = JO_MULT_BY_4096(palette_id);
    y = JO_DIV_BY_8(img->height);
    x = JO_DIV_BY_8(img->width);
    JO_ZERO(y2);
    JO_ZERO(x2);
    for (JO_ZERO(i); i < MAP_LENGTH; ++i)
    {
/*
        if (i != 0 && JO_MOD_POW2(i, CELL_COUNT_PER_ROW) == 0)
            ++y2;
        if (y2 >= y)
            JO_ZERO(y2);
        *map = (JO_MULT_BY_2(x2 + y2 * y) | paloff) + map_offset;
            ++map;
        ++x2;
        if (x2 >= x)
            JO_ZERO(y2);

/**/
        if (i != 0 && JO_MOD_POW2(i, CELL_COUNT_PER_ROW) == 0) {
            JO_ZERO(x2);
            ++y2;
            /*
            if (y2 >= y) {
                JO_ZERO(y2);
            }*/
        }
        *map = (JO_MULT_BY_2(x2 + y2 * x) | paloff) + map_offset;
        
        ++map;
        ++x2;
/**/        
    }
}

7

General Jo Engine Help / Re: TGA 8-bit in background

« Last post by FranMatsusaka on January 22, 2022, 09:20:25 pm »

Palette fixed:

8

General Jo Engine Help / Re: TGA 8-bit in background

« Last post by FranMatsusaka on January 22, 2022, 06:03:39 pm »

Check the "demo - vdp2 plane".

While not exactly what you want, it does demonstrate the process of loading an indexed color targa file to a VDP2 background layer.
You could copy this structure entirely, and simply not rotate the background layer.

Thank you very much! I fell a little silly because I couldn't find that jo_set_background_8bits_sprite by myself... Anyway, I have removed old code and substituted by all 8bit versions. I have not worked properly on the palette yet, but besides that it looks like there's some kind of corruption.

Here's the old code commented and the new:

Code: [Select]

        //jo_img  bg;
        //bg.data = NULL;
        //jo_tga_loader(&bg, "BGO", image_to_load, JO_COLOR_Transparent);
        //if (bg.data != NULL) {
            //jo_set_background_sprite(&bg, 0, 0);
            //jo_free_img(&bg);
        //}
        
        jo_img_8bits bg;
        bg.data = NULL;
        jo_tga_8bits_loader(&bg, "BG8", image_to_load, JO_COLOR_Transparent);
        
        if (bg.data != NULL) {
            jo_set_background_8bits_sprite(&bg, 0, false);
            jo_free_img(&bg);
        }

And here's te result... it looks like the tiles are displayed with some extra offset. Also, it looks like the tiles are 90º rotated


This is the original TGA in case anybody wants to check
https://drive.google.com/file/d/1qvcGEQqIViJUClh37X4_T9KCrY5eNPUk/view?usp=sharing

9

General Jo Engine Help / Re: TGA 8-bit in background

« Last post by ponut64 on January 21, 2022, 11:07:40 pm »

Check the "demo - vdp2 plane".

While not exactly what you want, it does demonstrate the process of loading an indexed color targa file to a VDP2 background layer.
You could copy this structure entirely, and simply not rotate the background layer.

10

General Jo Engine Help / TGA 8-bit in background

« Last post by FranMatsusaka on January 19, 2022, 10:50:41 am »

Hi,

I'm doing a Resident Evil like game, with 3d characters moving on a prerendered backgound, and I'm finding memory out problems.
I've seen that 8bit sprite is implemented and working, but I couldn't find a way to load TGA 8bit background. I've seen that there's a jo_img_8bits object type, and a jo_set_background_8bits_sprite, but I couldn't find a 8bit version of jo_tga_loader function. How can I load a 8bit TGA into a jo_img_8bits object?

Thanks in advance.