From 54b55c8da0afc923129163e1d5ab0ec1fcbffd86 Mon Sep 17 00:00:00 2001
From: Kostya Shishkov <kostya.shishkov@gmail.com>
Date: Thu, 7 Sep 2006 04:01:42 +0000
Subject: [PATCH] Cursor drawing support

Originally committed as revision 6183 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavcodec/vmnc.c | 172 ++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 167 insertions(+), 5 deletions(-)

diff --git a/libavcodec/vmnc.c b/libavcodec/vmnc.c
index a39bf271f0..ac50221c2e 100644
--- a/libavcodec/vmnc.c
+++ b/libavcodec/vmnc.c
@@ -60,6 +60,13 @@ typedef struct VmncContext {
     int bigendian;
     uint8_t pal[768];
     int width, height;
+
+    /* cursor data */
+    int cur_w, cur_h;
+    int cur_x, cur_y;
+    int cur_hx, cur_hy;
+    uint8_t* curbits, *curmask;
+    uint8_t* screendta;
 } VmncContext;
 
 /* read pixel value from stream */
@@ -75,6 +82,93 @@ static always_inline int vmnc_get_pixel(uint8_t* buf, int bpp, int be) {
     }
 }
 
+static void load_cursor(VmncContext *c, uint8_t *src)
+{
+    int i, j, p;
+    const int bpp = c->bpp2;
+    uint8_t  *dst8  = c->curbits;
+    uint16_t *dst16 = (uint16_t*)c->curbits;
+    uint32_t *dst32 = (uint32_t*)c->curbits;
+
+    for(j = 0; j < c->cur_h; j++) {
+        for(i = 0; i < c->cur_w; i++) {
+            p = vmnc_get_pixel(src, bpp, c->bigendian);
+            src += bpp;
+            if(bpp == 1) *dst8++ = p;
+            if(bpp == 2) *dst16++ = p;
+            if(bpp == 4) *dst32++ = p;
+        }
+    }
+    dst8 = c->curmask;
+    dst16 = (uint16_t*)c->curmask;
+    dst32 = (uint32_t*)c->curmask;
+    for(j = 0; j < c->cur_h; j++) {
+        for(i = 0; i < c->cur_w; i++) {
+            p = vmnc_get_pixel(src, bpp, c->bigendian);
+            src += bpp;
+            if(bpp == 1) *dst8++ = p;
+            if(bpp == 2) *dst16++ = p;
+            if(bpp == 4) *dst32++ = p;
+        }
+    }
+}
+
+static void put_cursor(uint8_t *dst, int stride, VmncContext *c, int dx, int dy)
+{
+    int i, j, t;
+    int w, h, x, y;
+    w = c->cur_w;
+    if(c->width < c->cur_x + c->cur_w) w = c->width - c->cur_x;
+    h = c->cur_h;
+    if(c->height < c->cur_y + c->cur_h) h = c->height - c->cur_y;
+    x = c->cur_x;
+    y = c->cur_y;
+    if(x < 0) {
+        w += x;
+        x = 0;
+    }
+    if(y < 0) {
+        h += y;
+        y = 0;
+    }
+
+    if((w < 1) || (h < 1)) return;
+    dst += x * c->bpp2 + y * stride;
+
+    if(c->bpp2 == 1) {
+        uint8_t* cd = c->curbits, *msk = c->curmask;
+        for(j = 0; j < h; j++) {
+            for(i = 0; i < w; i++)
+                dst[i] = (dst[i] & cd[i]) ^ msk[i];
+            msk += c->cur_w;
+            cd += c->cur_w;
+            dst += stride;
+        }
+    } else if(c->bpp2 == 2) {
+        uint16_t* cd = (uint16_t*)c->curbits, *msk = (uint16_t*)c->curmask;
+        uint16_t* dst2;
+        for(j = 0; j < h; j++) {
+            dst2 = (uint16_t*)dst;
+            for(i = 0; i < w; i++)
+                dst2[i] = (dst2[i] & cd[i]) ^ msk[i];
+            msk += c->cur_w;
+            cd += c->cur_w;
+            dst += stride;
+        }
+    } else if(c->bpp2 == 4) {
+        uint32_t* cd = (uint32_t*)c->curbits, *msk = (uint32_t*)c->curmask;
+        uint32_t* dst2;
+        for(j = 0; j < h; j++) {
+            dst2 = (uint32_t*)dst;
+            for(i = 0; i < w; i++)
+                dst2[i] = (dst2[i] & cd[i]) ^ msk[i];
+            msk += c->cur_w;
+            cd += c->cur_w;
+            dst += stride;
+        }
+    }
+}
+
 /* fill rectangle with given colour */
 static always_inline void paint_rect(uint8_t *dst, int dx, int dy, int w, int h, int color, int bpp, int stride)
 {
@@ -194,6 +288,31 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
     c->pic.key_frame = 0;
     c->pic.pict_type = FF_P_TYPE;
 
+    //restore screen after cursor
+    if(c->screendta) {
+        int i;
+        w = c->cur_w;
+        if(c->width < c->cur_x + w) w = c->width - c->cur_x;
+        h = c->cur_h;
+        if(c->height < c->cur_y + h) h = c->height - c->cur_y;
+        dx = c->cur_x;
+        if(dx < 0) {
+            w += dx;
+            dx = 0;
+        }
+        dy = c->cur_y;
+        if(dy < 0) {
+            h += dy;
+            dy = 0;
+        }
+        if((w > 0) && (h > 0)) {
+            outptr = c->pic.data[0] + dx * c->bpp2 + dy * c->pic.linesize[0];
+            for(i = 0; i < h; i++) {
+                memcpy(outptr, c->screendta + i * c->cur_w * c->bpp2, w * c->bpp2);
+                outptr += c->pic.linesize[0];
+            }
+        }
+    }
     src += 2;
     chunks = BE_16(src); src += 2;
     while(chunks--) {
@@ -202,15 +321,30 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
         w  = BE_16(src); src += 2;
         h  = BE_16(src); src += 2;
         enc = BE_32(src); src += 4;
+        outptr = c->pic.data[0] + dx * c->bpp2 + dy * c->pic.linesize[0];
         switch(enc) {
-        case MAGIC_WMVd: // unknown
+        case MAGIC_WMVd: // cursor
             src += 2;
-            src += w * h * 8; // skip this data for now
+            c->cur_w = w;
+            c->cur_h = h;
+            c->cur_hx = dx;
+            c->cur_hy = dy;
+            if((c->cur_hx > c->cur_w) || (c->cur_hy > c->cur_h)) {
+                av_log(avctx, AV_LOG_ERROR, "Cursor hot spot is not in image: %ix%i of %ix%i cursor size\n", c->cur_hx, c->cur_hy, c->cur_w, c->cur_h);
+                c->cur_hx = c->cur_hy = 0;
+            }
+            c->curbits = av_realloc(c->curbits, c->cur_w * c->cur_h * c->bpp2);
+            c->curmask = av_realloc(c->curmask, c->cur_w * c->cur_h * c->bpp2);
+            c->screendta = av_realloc(c->screendta, c->cur_w * c->cur_h * c->bpp2);
+            load_cursor(c, src);
+            src += w * h * c->bpp2 * 2;
             break;
         case MAGIC_WMVe: // unknown
             src += 2;
             break;
-        case MAGIC_WMVf: // unknown and empty
+        case MAGIC_WMVf: // update cursor position
+            c->cur_x = dx - c->cur_hx;
+            c->cur_y = dy - c->cur_hy;
             break;
         case MAGIC_WMVi: // ServerInitialization struct
             c->pic.key_frame = 1;
@@ -233,7 +367,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
                 av_log(avctx, AV_LOG_ERROR, "Incorrect frame size: %ix%i+%ix%i of %ix%i\n", w, h, dx, dy, c->width, c->height);
                 return -1;
             }
-            outptr = c->pic.data[0] + dx * c->bpp2 + dy * c->pic.linesize[0];
             paint_raw(outptr, w, h, src, c->bpp2, c->bigendian, c->pic.linesize[0]);
             src += w * h * c->bpp2;
             break;
@@ -242,7 +375,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
                 av_log(avctx, AV_LOG_ERROR, "Incorrect frame size: %ix%i+%ix%i of %ix%i\n", w, h, dx, dy, c->width, c->height);
                 return -1;
             }
-            outptr = c->pic.data[0] + dx * c->bpp2 + dy * c->pic.linesize[0];
             res = decode_hextile(c, outptr, src, w, h, c->pic.linesize[0]);
             if(res < 0)
                 return -1;
@@ -253,6 +385,33 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
             chunks = 0; // leave chunks decoding loop
         }
     }
+    if(c->screendta){
+        int i;
+        //save screen data before painting cursor
+        w = c->cur_w;
+        if(c->width < c->cur_x + w) w = c->width - c->cur_x;
+        h = c->cur_h;
+        if(c->height < c->cur_y + h) h = c->height - c->cur_y;
+        dx = c->cur_x;
+        if(dx < 0) {
+            w += dx;
+            dx = 0;
+        }
+        dy = c->cur_y;
+        if(dy < 0) {
+            h += dy;
+            dy = 0;
+        }
+        if((w > 0) && (h > 0)) {
+            outptr = c->pic.data[0] + dx * c->bpp2 + dy * c->pic.linesize[0];
+            for(i = 0; i < h; i++) {
+                memcpy(c->screendta + i * c->cur_w * c->bpp2, outptr, w * c->bpp2);
+                outptr += c->pic.linesize[0];
+            }
+            outptr = c->pic.data[0];
+            put_cursor(outptr, c->pic.linesize[0], c, c->cur_x, c->cur_y);
+        }
+    }
     *data_size = sizeof(AVFrame);
     *(AVFrame*)data = c->pic;
 
@@ -315,6 +474,9 @@ static int decode_end(AVCodecContext *avctx)
     if (c->pic.data[0])
         avctx->release_buffer(avctx, &c->pic);
 
+    av_free(c->curbits);
+    av_free(c->curmask);
+    av_free(c->screendta);
     return 0;
 }