pixman: render vgafont glyphs into pixman images

Add helper functions to create pixman mask images for glyphs
and to render these glyphs into a pixman image.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

2 files changed, 50 insertions, 0 deletions

diff --git a/include/ui/qemu-pixman.h b/include/ui/qemu-pixman.h
index b0f09b587f..f012ec5fc3 100644
--- a/include/ui/qemu-pixman.h
+++ b/include/ui/qemu-pixman.h
@@ -44,5 +44,12 @@ pixman_image_t *qemu_pixman_mirror_create(pixman_format_code_t format,
 void qemu_pixman_image_unref(pixman_image_t *image);
 
 pixman_color_t qemu_pixman_color(PixelFormat *pf, uint32_t color);
+pixman_image_t *qemu_pixman_glyph_from_vgafont(int height, const uint8_t *font,
+                                               unsigned int ch);
+void qemu_pixman_glyph_render(pixman_image_t *glyph,
+                              pixman_image_t *surface,
+                              pixman_color_t *fgcol,
+                              pixman_color_t *bgcol,
+                              int x, int y, int cw, int ch);
 
 #endif /* QEMU_PIXMAN_H */
diff --git a/ui/qemu-pixman.c b/ui/qemu-pixman.c
index be551e09ed..254bd8ce10 100644
--- a/ui/qemu-pixman.c
+++ b/ui/qemu-pixman.c
@@ -90,3 +90,46 @@ pixman_color_t qemu_pixman_color(PixelFormat *pf, uint32_t color)
     c.alpha = ((color & pf->amask) >> pf->ashift) << (16 - pf->abits);
     return c;
 }
+
+pixman_image_t *qemu_pixman_glyph_from_vgafont(int height, const uint8_t *font,
+                                               unsigned int ch)
+{
+    pixman_image_t *glyph;
+    uint8_t *data;
+    bool bit;
+    int x, y;
+
+    glyph = pixman_image_create_bits(PIXMAN_a8, 8, height,
+                                     NULL, 0);
+    data = (uint8_t *)pixman_image_get_data(glyph);
+
+    font += height * ch;
+    for (y = 0; y < height; y++, font++) {
+        for (x = 0; x < 8; x++, data++) {
+            bit = (*font) & (1 << (7-x));
+            *data = bit ? 0xff : 0x00;
+        }
+    }
+    return glyph;
+}
+
+void qemu_pixman_glyph_render(pixman_image_t *glyph,
+                              pixman_image_t *surface,
+                              pixman_color_t *fgcol,
+                              pixman_color_t *bgcol,
+                              int x, int y, int cw, int ch)
+{
+    pixman_image_t *ifg = pixman_image_create_solid_fill(fgcol);
+    pixman_image_t *ibg = pixman_image_create_solid_fill(bgcol);
+
+    pixman_image_composite(PIXMAN_OP_SRC, ibg, NULL, surface,
+                           0, 0, 0, 0,
+                           cw * x, ch * y,
+                           cw, ch);
+    pixman_image_composite(PIXMAN_OP_OVER, ifg, glyph, surface,
+                           0, 0, 0, 0,
+                           cw * x, ch * y,
+                           cw, ch);
+    pixman_image_unref(ifg);
+    pixman_image_unref(ibg);
+}