gfx_image.c

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/* image create/destroy functions */

#include "fb_gfx.h"

static void *gfx_imagecreate(int width, int height, unsigned int color, int depth, int flags, int usenewheader)
{
        FB_GFXCTX *context = fb_hGetContext();
        PUT_HEADER *image;
        int size, pitch, header_size = 4;
        int bpp;

        if ((!__fb_gfx) || (width <= 0) || (height <= 0)) {
                fb_ErrorSetNum( FB_RTERROR_ILLEGALFUNCTIONCALL );
                return NULL;
        }

        if (depth > 0) {
                bpp = BYTES_PER_PIXEL(depth);
                if ((bpp != 1) && (bpp != 2) && (bpp != 4)) {
                        fb_ErrorSetNum( FB_RTERROR_ILLEGALFUNCTIONCALL );
                        return NULL;
                }
        }
        else
                bpp = __fb_gfx->bpp;

        if (flags & DEFAULT_COLOR_1) {
                switch (bpp) {
                        case 1: color = 0; break;
                        case 2: color = MASK_COLOR_16; break;
                        case 4: color = MASK_COLOR_32 | MASK_A_32; break;
                }
        }
        else {
                if (bpp == 2)
                        color = ((color & 0xF8) >> 3) | ((color & 0xFC00) >> 5) | ((color & 0xF80000) >> 8);
        }

        pitch = width * bpp;
        if (usenewheader) {
                header_size = sizeof(PUT_HEADER);
                pitch = (pitch + 0xF) & ~0xF;
        }
        size = pitch * height;

        /* 0xF for the para alignment, p_size is sizeof(void *) rounded up to % 16 for the storage for the original pointer */
        int p_size = (sizeof(void *) + 0xF) & 0xF;
        void *tmp = malloc(size + header_size + p_size + 0xF);
        if (tmp == NULL) {
                fb_ErrorSetNum( FB_RTERROR_OUTOFMEM );
                return NULL;
        }

        image = (PUT_HEADER *)(((intptr_t)tmp + p_size + 0xF) & ~0xF);
        ((void **)image)[-1] = tmp;

        if (!usenewheader) {
                /* use old-style header for compatibility */
                image->old.bpp = bpp;
                image->old.width = width;
                image->old.height = height;
        }
        else {
                image->type = PUT_HEADER_NEW;
                image->bpp = bpp;
                image->width = width;
                image->height = height;
                image->pitch = pitch;
                fb_hMemSet(image->_reserved, 0, sizeof(image->_reserved));
        }
        fb_hPrepareTarget(context, (void *)image);
        fb_hSetPixelTransfer(context, MASK_A_32);
        context->pixel_set((unsigned char *)image + header_size, color, (pitch * height) / bpp);

        fb_ErrorSetNum( FB_RTERROR_OK );
        return image;
}

FBCALL void *fb_GfxImageCreate(int width, int height, unsigned int color, int depth, int flags)
{
        return gfx_imagecreate( width, height, color, depth, flags, TRUE );
}

FBCALL void *fb_GfxImageCreateQB(int width, int height, unsigned int color, int depth, int flags)
{
        return gfx_imagecreate( width, height, color, depth, flags, FALSE );
}

FBCALL void fb_GfxImageDestroy(void *image)
{
        if( image == NULL ) return;
        free(((void **)image)[-1]);
}