lcd: Support colour lookup table on 16bpp display in BMP images

For 16-bit-per-pixel displays it is useful to support 8 bit-per-pixel
images to reduce image size. Add support for this when drawing BMP images.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/common/lcd.c b/common/lcd.c
index c7f2830..5a52fe4 100644 (file)
--- a/common/lcd.c
+++ b/common/lcd.c
@@ -578,6 +578,8 @@ int lcd_display_bitmap(ulong bmp_image, int x, int y)
        unsigned long width, height, byte_width;
        unsigned long pwidth = panel_info.vl_col;
        unsigned colors, bpix, bmp_bpix;
+       int hdr_size;
+       struct bmp_color_table_entry *palette = bmp->color_table;
 
        if (!bmp || !(bmp->header.signature[0] == 'B' &&
                bmp->header.signature[1] == 'M')) {
@@ -589,6 +591,8 @@ int lcd_display_bitmap(ulong bmp_image, int x, int y)
        width = get_unaligned_le32(&bmp->header.width);
        height = get_unaligned_le32(&bmp->header.height);
        bmp_bpix = get_unaligned_le16(&bmp->header.bit_count);
+       hdr_size = get_unaligned_le16(&bmp->header.size);
+       debug("hdr_size=%d, bmp_bpix=%d\n", hdr_size, bmp_bpix);
 
        colors = 1 << bmp_bpix;
 
@@ -613,8 +617,8 @@ int lcd_display_bitmap(ulong bmp_image, int x, int y)
                return 1;
        }
 
-       debug("Display-bmp: %d x %d  with %d colors\n",
-               (int)width, (int)height, (int)colors);
+       debug("Display-bmp: %d x %d  with %d colors, display %d\n",
+             (int)width, (int)height, (int)colors, 1 << bpix);
 
        if (bmp_bpix == 8)
                lcd_set_cmap(bmp, colors);
@@ -641,6 +645,7 @@ int lcd_display_bitmap(ulong bmp_image, int x, int y)
                cmap_base = configuration_get_cmap();
 #ifdef CONFIG_LCD_BMP_RLE8
                u32 compression = get_unaligned_le32(&bmp->header.compression);
+               debug("compressed %d %d\n", compression, BMP_BI_RLE8);
                if (compression == BMP_BI_RLE8) {
                        if (bpix != 16) {
                                /* TODO implement render code for bpix != 16 */
@@ -663,7 +668,19 @@ int lcd_display_bitmap(ulong bmp_image, int x, int y)
                                if (bpix != 16) {
                                        fb_put_byte(&fb, &bmap);
                                } else {
-                                       *(uint16_t *)fb = cmap_base[*(bmap++)];
+                                       struct bmp_color_table_entry *entry;
+                                       uint val;
+
+                                       if (cmap_base) {
+                                               val = cmap_base[*bmap];
+                                       } else {
+                                               entry = &palette[*bmap];
+                                               val = entry->blue >> 3 |
+                                                       entry->green >> 2 << 5 |
+                                                       entry->red >> 3 << 11;
+                                       }
+                                       *(uint16_t *)fb = val;
+                                       bmap++;
                                        fb += sizeof(uint16_t) / sizeof(*fb);
                                }
                        }