libui/unix/image.c

135 lines
2.9 KiB
C

// 27 june 2016
#include "uipriv_unix.h"
struct uiImage {
double width;
double height;
GPtrArray *images;
};
static void freeImageRep(gpointer item)
{
cairo_surface_t *cs = (cairo_surface_t *) item;
cairo_surface_destroy(cs);
}
uiImage *uiNewImage(double width, double height)
{
uiImage *i;
i = uiprivNew(uiImage);
i->width = width;
i->height = height;
i->images = g_ptr_array_new_with_free_func(freeImageRep);
return i;
}
void uiFreeImage(uiImage *i)
{
g_ptr_array_free(i->images, TRUE);
uiprivFree(i);
}
void uiImageAppend(uiImage *i, void *pixels, int pixelWidth, int pixelHeight, int byteStride)
{
cairo_surface_t *cs;
uint8_t *data, *pix;
int realStride;
int x, y;
// note that this is native-endian
cs = cairo_image_surface_create(CAIRO_FORMAT_ARGB32,
pixelWidth, pixelHeight);
if (cairo_surface_status(cs) != CAIRO_STATUS_SUCCESS)
/* TODO */;
cairo_surface_flush(cs);
pix = (uint8_t *) pixels;
data = (uint8_t *) cairo_image_surface_get_data(cs);
realStride = cairo_image_surface_get_stride(cs);
for (y = 0; y < pixelHeight; y++) {
for (x = 0; x < pixelWidth * 4; x += 4) {
union {
uint32_t v32;
uint8_t v8[4];
} v;
v.v32 = ((uint32_t) (pix[x + 3])) << 24;
v.v32 |= ((uint32_t) (pix[x])) << 16;
v.v32 |= ((uint32_t) (pix[x + 1])) << 8;
v.v32 |= ((uint32_t) (pix[x + 2]));
data[x] = v.v8[0];
data[x + 1] = v.v8[1];
data[x + 2] = v.v8[2];
data[x + 3] = v.v8[3];
}
pix += byteStride;
data += realStride;
}
cairo_surface_mark_dirty(cs);
g_ptr_array_add(i->images, cs);
}
struct matcher {
cairo_surface_t *best;
int distX;
int distY;
int targetX;
int targetY;
gboolean foundLarger;
};
// TODO is this the right algorithm?
static void match(gpointer surface, gpointer data)
{
cairo_surface_t *cs = (cairo_surface_t *) surface;
struct matcher *m = (struct matcher *) data;
int x, y;
int x2, y2;
x = cairo_image_surface_get_width(cs);
y = cairo_image_surface_get_height(cs);
if (m->best == NULL)
goto writeMatch;
if (x < m->targetX && y < m->targetY)
if (m->foundLarger)
// always prefer larger ones
return;
if (x >= m->targetX && y >= m->targetY && !m->foundLarger)
// we set foundLarger below
goto writeMatch;
x2 = abs(m->targetX - x);
y2 = abs(m->targetY - y);
if (x2 < m->distX && y2 < m->distY)
goto writeMatch;
// TODO weight one dimension? threshhold?
return;
writeMatch:
// must set this here too; otherwise the first image will never have ths set
if (x >= m->targetX && y >= m->targetY && !m->foundLarger)
m->foundLarger = TRUE;
m->best = cs;
m->distX = abs(m->targetX - x);
m->distY = abs(m->targetY - y);
}
cairo_surface_t *uiprivImageAppropriateSurface(uiImage *i, GtkWidget *w)
{
struct matcher m;
m.best = NULL;
m.distX = G_MAXINT;
m.distY = G_MAXINT;
m.targetX = i->width * gtk_widget_get_scale_factor(w);
m.targetY = i->height * gtk_widget_get_scale_factor(w);
m.foundLarger = FALSE;
g_ptr_array_foreach(i->images, match, &m);
return m.best;
}