source: mainline/uspace/lib/guigfx/src/canvas.c@ 7b882c1f

/*
 * Copyright (c) 2019 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libguigfx
 * @{
 */
/**
 * @file GFX canvas backend
 *
 * This implements a graphics context over a libgui canvas.
 * This is just for experimentation purposes and its kind of backwards.
 */

#include <draw/drawctx.h>
#include <draw/source.h>
#include <gfx/color.h>
#include <gfx/context.h>
#include <gfx/render.h>
#include <guigfx/canvas.h>
#include <io/pixel.h>
#include <stdlib.h>
#include <transform.h>
#include "../private/canvas.h"
//#include "../../private/color.h"

static errno_t canvas_gc_set_color(void *, gfx_color_t *);
static errno_t canvas_gc_fill_rect(void *, gfx_rect_t *);
static errno_t canvas_gc_bitmap_create(void *, gfx_bitmap_params_t *,
    gfx_bitmap_alloc_t *, void **);
static errno_t canvas_gc_bitmap_destroy(void *);
static errno_t canvas_gc_bitmap_render(void *, gfx_rect_t *, gfx_coord2_t *);
static errno_t canvas_gc_bitmap_get_alloc(void *, gfx_bitmap_alloc_t *);

gfx_context_ops_t canvas_gc_ops = {
        .set_color = canvas_gc_set_color,
        .fill_rect = canvas_gc_fill_rect,
        .bitmap_create = canvas_gc_bitmap_create,
        .bitmap_destroy = canvas_gc_bitmap_destroy,
        .bitmap_render = canvas_gc_bitmap_render,
        .bitmap_get_alloc = canvas_gc_bitmap_get_alloc
};

/** Set color on canvas GC.
 *
 * Set drawing color on canvas GC.
 *
 * @param arg Canvas GC
 * @param color Color
 *
 * @return EOK on success or an error code
 */
static errno_t canvas_gc_set_color(void *arg, gfx_color_t *color)
{
        canvas_gc_t *cgc = (canvas_gc_t *) arg;
        uint16_t r, g, b;

        gfx_color_get_rgb_i16(color, &r, &g, &b);
        cgc->color = PIXEL(0, r >> 8, g >> 8, b >> 8);
        return EOK;
}

/** Fill rectangle on canvas GC.
 *
 * @param arg Canvas GC
 * @param rect Rectangle
 *
 * @return EOK on success or an error code
 */
static errno_t canvas_gc_fill_rect(void *arg, gfx_rect_t *rect)
{
        canvas_gc_t *cgc = (canvas_gc_t *) arg;
        gfx_coord_t x, y;

        // XXX We should handle p0.x > p1.x and p0.y > p1.y

        for (y = rect->p0.y; y < rect->p1.y; y++) {
                for (x = rect->p0.x; x < rect->p1.x; x++) {
                        surface_put_pixel(cgc->surface, x, y, cgc->color);
                }
        }

        update_canvas(cgc->canvas, cgc->surface);

        return EOK;
}

/** Create canvas GC.
 *
 * Create graphics context for rendering into a canvas.
 *
 * @param con Canvas object
 * @param fout File to which characters are written (canvas)
 * @param rgc Place to store pointer to new GC.
 *
 * @return EOK on success or an error code
 */
errno_t canvas_gc_create(canvas_t *canvas, surface_t *surface,
    canvas_gc_t **rgc)
{
        canvas_gc_t *cgc = NULL;
        gfx_context_t *gc = NULL;
        errno_t rc;

        cgc = calloc(1, sizeof(canvas_gc_t));
        if (cgc == NULL) {
                rc = ENOMEM;
                goto error;
        }

        rc = gfx_context_new(&canvas_gc_ops, cgc, &gc);
        if (rc != EOK)
                goto error;

        cgc->gc = gc;
        cgc->canvas = canvas;
        cgc->surface = surface;
        *rgc = cgc;
        return EOK;
error:
        if (cgc != NULL)
                free(cgc);
        gfx_context_delete(gc);
        return rc;
}

/** Delete canvas GC.
 *
 * @param cgc Canvas GC
 */
errno_t canvas_gc_delete(canvas_gc_t *cgc)
{
        errno_t rc;

        rc = gfx_context_delete(cgc->gc);
        if (rc != EOK)
                return rc;

        free(cgc);
        return EOK;
}

/** Get generic graphic context from canvas GC.
 *
 * @param cgc Canvas GC
 * @return Graphic context
 */
gfx_context_t *canvas_gc_get_ctx(canvas_gc_t *cgc)
{
        return cgc->gc;
}

/** Create bitmap in canvas GC.
 *
 * @param arg Canvas GC
 * @param params Bitmap params
 * @param alloc Bitmap allocation info or @c NULL
 * @param rbm Place to store pointer to new bitmap
 * @return EOK on success or an error code
 */
errno_t canvas_gc_bitmap_create(void *arg, gfx_bitmap_params_t *params,
    gfx_bitmap_alloc_t *alloc, void **rbm)
{
        canvas_gc_t *cgc = (canvas_gc_t *) arg;
        canvas_gc_bitmap_t *cbm = NULL;
        gfx_coord2_t dim;
        errno_t rc;

        cbm = calloc(1, sizeof(canvas_gc_bitmap_t));
        if (cbm == NULL)
                return ENOMEM;

        gfx_coord2_subtract(&params->rect.p1, &params->rect.p0, &dim);
        cbm->rect = params->rect;

        if (alloc == NULL) {
                cbm->surface = surface_create(dim.x, dim.y, NULL, 0);
                if (cbm->surface == NULL) {
                        rc = ENOMEM;
                        goto error;
                }

                cbm->alloc.pitch = dim.x * sizeof(uint32_t);
                cbm->alloc.off0 = 0;
                cbm->alloc.pixels = surface_direct_access(cbm->surface);
                cbm->myalloc = true;
        } else {
                cbm->surface = surface_create(dim.x, dim.y, alloc->pixels, 0);
                if (cbm->surface == NULL) {
                        rc = ENOMEM;
                        goto error;
                }

                cbm->alloc = *alloc;
        }

        cbm->cgc = cgc;
        *rbm = (void *)cbm;
        return EOK;
error:
        if (cbm != NULL)
                free(cbm);
        return rc;
}

/** Destroy bitmap in canvas GC.
 *
 * @param bm Bitmap
 * @return EOK on success or an error code
 */
static errno_t canvas_gc_bitmap_destroy(void *bm)
{
        canvas_gc_bitmap_t *cbm = (canvas_gc_bitmap_t *)bm;
        if (cbm->myalloc)
                surface_destroy(cbm->surface);
        // XXX if !cbm->myalloc, surface is leaked - no way to destroy it
        // without destroying the pixel buffer
        free(cbm);
        return EOK;
}

/** Render bitmap in canvas GC.
 *
 * @param bm Bitmap
 * @param srect0 Source rectangle or @c NULL
 * @param offs0 Offset or @c NULL
 * @return EOK on success or an error code
 */
static errno_t canvas_gc_bitmap_render(void *bm, gfx_rect_t *srect0,
    gfx_coord2_t *offs0)
{
        canvas_gc_bitmap_t *cbm = (canvas_gc_bitmap_t *)bm;
        gfx_rect_t srect;
        gfx_rect_t drect;
        gfx_coord2_t offs;
        gfx_coord2_t dim;

        if (srect0 != NULL)
                srect = *srect0;
        else
                srect = cbm->rect;

        if (offs0 != NULL) {
                offs = *offs0;
        } else {
                offs.x = 0;
                offs.y = 0;
        }

        /* Destination rectangle */
        gfx_rect_translate(&offs, &srect, &drect);

        gfx_coord2_subtract(&drect.p1, &drect.p0, &dim);

        transform_t transform;
        transform_identity(&transform);
        transform_translate(&transform, offs.x - cbm->rect.p0.x,
            offs.y - cbm->rect.p0.y);

        source_t source;
        source_init(&source);
        source_set_transform(&source, transform);
        source_set_texture(&source, cbm->surface,
            PIXELMAP_EXTEND_TRANSPARENT_BLACK);

        drawctx_t drawctx;
        drawctx_init(&drawctx, cbm->cgc->surface);

        drawctx_set_source(&drawctx, &source);
        drawctx_transfer(&drawctx, drect.p0.x, drect.p0.y, dim.x, dim.y);

        update_canvas(cbm->cgc->canvas, cbm->cgc->surface);
        return EOK;
}

/** Get allocation info for bitmap in canvas GC.
 *
 * @param bm Bitmap
 * @param alloc Place to store allocation info
 * @return EOK on success or an error code
 */
static errno_t canvas_gc_bitmap_get_alloc(void *bm, gfx_bitmap_alloc_t *alloc)
{
        canvas_gc_bitmap_t *cbm = (canvas_gc_bitmap_t *)bm;
        *alloc = cbm->alloc;
        return EOK;
}

/** @}
 */