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/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <stdlib.h>
void vp8_blit_text(const char *msg, unsigned char *address, const int pitch)
{
int letter_bitmap;
unsigned char *output_pos = address;
int colpos;
const int font[] =
{
0x0, 0x5C00, 0x8020, 0xAFABEA, 0xD7EC0, 0x1111111, 0x1855740, 0x18000,
0x45C0, 0x74400, 0x51140, 0x23880, 0xC4000, 0x21080, 0x80000, 0x111110,
0xE9D72E, 0x87E40, 0x12AD732, 0xAAD62A, 0x4F94C4, 0x4D6B7, 0x456AA,
0x3E8423, 0xAAD6AA, 0xAAD6A2, 0x2800, 0x2A00, 0x8A880, 0x52940, 0x22A20,
0x15422, 0x6AD62E, 0x1E4A53E, 0xAAD6BF, 0x8C62E, 0xE8C63F, 0x118D6BF,
0x1094BF, 0xCAC62E, 0x1F2109F, 0x118FE31, 0xF8C628, 0x8A89F, 0x108421F,
0x1F1105F, 0x1F4105F, 0xE8C62E, 0x2294BF, 0x164C62E, 0x12694BF, 0x8AD6A2,
0x10FC21, 0x1F8421F, 0x744107, 0xF8220F, 0x1151151, 0x117041, 0x119D731,
0x47E0, 0x1041041, 0xFC400, 0x10440, 0x1084210, 0x820
};
colpos = 0;
while (msg[colpos] != 0)
{
char letter = msg[colpos];
int fontcol, fontrow;
if (letter <= 'Z' && letter >= ' ')
letter_bitmap = font[letter-' '];
else if (letter <= 'z' && letter >= 'a')
letter_bitmap = font[letter-'a'+'A' - ' '];
else
letter_bitmap = font[0];
for (fontcol = 6; fontcol >= 0 ; fontcol--)
for (fontrow = 0; fontrow < 5; fontrow++)
output_pos[fontrow *pitch + fontcol] =
((letter_bitmap >> (fontcol * 5)) & (1 << fontrow) ? 255 : 0);
output_pos += 7;
colpos++;
}
}
static void plot (const int x, const int y, unsigned char *image, const int pitch)
{
image [x+y*pitch] ^= 255;
}
// Bresenham line algorithm
void vp8_blit_line(int x0, int x1, int y0, int y1, unsigned char *image, const int pitch)
{
int steep = abs(y1 - y0) > abs(x1 - x0);
int deltax, deltay;
int error, ystep, y, x;
if (steep)
{
int t;
t = x0;
x0 = y0;
y0 = t;
t = x1;
x1 = y1;
y1 = t;
}
if (x0 > x1)
{
int t;
t = x0;
x0 = x1;
x1 = t;
t = y0;
y0 = y1;
y1 = t;
}
deltax = x1 - x0;
deltay = abs(y1 - y0);
error = deltax / 2;
y = y0;
if (y0 < y1)
ystep = 1;
else
ystep = -1;
if (steep)
{
for (x = x0; x <= x1; x++)
{
plot(y,x, image, pitch);
error = error - deltay;
if (error < 0)
{
y = y + ystep;
error = error + deltax;
}
}
}
else
{
for (x = x0; x <= x1; x++)
{
plot(x,y, image, pitch);
error = error - deltay;
if (error < 0)
{
y = y + ystep;
error = error + deltax;
}
}
}
}
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