vid_voodoo_banshee: Implement gamma correction for 16bpp

Cacodemon345 · Dec 30, 2023 · ddb43a7 · ddb43a7
1 parent de2f347
commit ddb43a7
Showing 1 changed file with 32 additions and 1 deletion.
diff --git a/src/video/vid_voodoo_banshee.c b/src/video/vid_voodoo_banshee.c
@@ -219,7 +219,9 @@ enum {
 #define VIDPROCCFG_INTERLACE                (1 << 3)
 #define VIDPROCCFG_HALF_MODE                (1 << 4)
 #define VIDPROCCFG_OVERLAY_ENABLE           (1 << 8)
+#define VIDPROCCFG_DESKTOP_CLUT_BYPASS      (1 << 10)
 #define VIDPROCCFG_OVERLAY_CLUT_BYPASS      (1 << 11)
+#define VIDPROCCFG_DESKTOP_CLUT_SEL         (1 << 12)
 #define VIDPROCCFG_OVERLAY_CLUT_SEL         (1 << 13)
 #define VIDPROCCFG_H_SCALE_ENABLE           (1 << 14)
 #define VIDPROCCFG_V_SCALE_ENABLE           (1 << 15)
@@ -466,6 +468,32 @@ banshee_updatemapping(banshee_t *banshee)
     mem_mapping_set_addr(&banshee->reg_mapping_high, banshee->memBaseAddr0 + 0xc00000, 20 << 20);
 }
 
+uint32_t
+banshee_conv_16to32(svga_t* svga, uint16_t color, uint8_t bpp)
+{
+    banshee_t *banshee = (banshee_t *) svga->priv;
+    uint32_t ret = 0x00000000;
+    uint16_t src_b = (color & 0x1f) << 3;
+    uint16_t src_g = (color & 0x7e0) >> 3;
+    uint16_t src_r = (color & 0xf800) >> 8;
+
+    if (banshee->vidProcCfg & VIDPROCCFG_DESKTOP_CLUT_SEL) {
+        src_b += 256;
+        src_g += 256;
+        src_r += 256;
+    }
+
+    if (svga->lut_map) {
+        uint8_t b = getcolr(svga->pallook[src_b]);
+        uint8_t g = getcolg(svga->pallook[src_g]);
+        uint8_t r = getcolb(svga->pallook[src_r]);
+        ret = (video_16to32[color] & 0xFF000000) | makecol(r, g, b);
+    } else
+        ret = video_16to32[color];
+
+    return ret;
+}
+
 static void
 banshee_render_16bpp_tiled(svga_t *svga)
 {
@@ -489,7 +517,7 @@ banshee_render_16bpp_tiled(svga_t *svga)
             const uint16_t *vram_p = (uint16_t *) &svga->vram[addr & svga->vram_display_mask];
 
             for (uint8_t xx = 0; xx < 64; xx++)
-                *p++ = video_16to32[*vram_p++];
+                *p++ = banshee_conv_16to32(svga, *vram_p++, 16);
 
             drawn = 1;
         } else
@@ -806,6 +834,7 @@ banshee_ext_outl(uint16_t addr, uint32_t val, void *priv)
             banshee->overlay_pix_fmt = (val & VIDPROCCFG_OVERLAY_PIX_FORMAT_MASK) >> VIDPROCCFG_OVERLAY_PIX_FORMAT_SHIFT;
             svga->hwcursor.ena       = val & VIDPROCCFG_HWCURSOR_ENA;
             svga->fullchange         = changeframecount;
+            svga->lut_map            = !(val & VIDPROCCFG_DESKTOP_CLUT_BYPASS) && (svga->bpp < 24);
             svga_recalctimings(svga);
             break;
 
@@ -3190,6 +3219,8 @@ banshee_init_common(const device_t *info, char *fn, int has_sgram, int type, int
     banshee->i2c_ddc = i2c_gpio_init("ddc_voodoo_banshee");
     banshee->ddc     = ddc_init(i2c_gpio_get_bus(banshee->i2c_ddc));
 
+    banshee->svga.conv_16to32 = banshee_conv_16to32;
+
     switch (type) {
         case TYPE_BANSHEE:
             if (has_sgram) {