| 1 | ␊ |
| 2 | /* Graphic utility functions and data types␊ |
| 3 | * Prashant Vaibhav (C) 12/12/2008␊ |
| 4 | * Chameleon␊ |
| 5 | */␊ |
| 6 | #include "boot.h"␊ |
| 7 | #include "graphic_utils.h"␊ |
| 8 | #include "gui.h"␊ |
| 9 | ␊ |
| 10 | void blend( const pixmap_t *blendThis,␉␉// Source image␊ |
| 11 | ␉␉pixmap_t *blendInto,␉␉// Dest image␊ |
| 12 | ␉␉const position_t position)␉// Where to place the source image␊ |
| 13 | {␊ |
| 14 | uint16_t sx, sy, dx, dy;␊ |
| 15 | uint32_t dstrb, dstag, srcrb, srcag, drb, dag, rb, ag, alpha;␊ |
| 16 | ␉␊ |
| 17 | ␉uint16_t width = (blendThis->width + position.x < blendInto->width) ? blendThis->width: blendInto->width-position.x;␊ |
| 18 | ␉uint16_t height = (blendThis->height + position.y < blendInto->height) ? blendThis->height: blendInto->height-position.y;␊ |
| 19 | ␉␊ |
| 20 | ␉for (dy = position.y, sy = 0; sy < height; dy++, sy++) {␊ |
| 21 | ␉␉for (dx = position.x, sx = 0; sx < width; dx++, sx++) {␊ |
| 22 | ␉␉␉alpha = (pixel(blendThis, sx, sy).ch.a);␊ |
| 23 | ␊ |
| 24 | ␉␉␉/* Skip blending for fully transparent pixel */␊ |
| 25 | ␉␉␉if (alpha == 0) {␊ |
| 26 | ␉␉␉␉continue;␊ |
| 27 | ␉␉␉}␊ |
| 28 | ␊ |
| 29 | ␉␉␉/* For fully opaque pixel, there is no need to interpolate */␊ |
| 30 | ␉␉␉if (alpha == 255) {␊ |
| 31 | ␉␉␉␉pixel(blendInto, dx, dy).value = pixel(blendThis, sx, sy).value;␊ |
| 32 | ␉␉␉␉continue;␊ |
| 33 | ␉␉␉}␊ |
| 34 | ␊ |
| 35 | ␉␉␉/* For semi-transparent pixels, do a full blend */␊ |
| 36 | ␉␉␉//alpha++␊ |
| 37 | ␉␉␉/* This is needed to spread the alpha over [0..256] instead of [0..255]␊ |
| 38 | ␉␉␉Boundary conditions were handled above */␊ |
| 39 | ␉␉␉dstrb = pixel(blendInto, dx, dy).value & 0xFF00FF;␊ |
| 40 | ␉␉␉dstag = (pixel(blendInto, dx, dy).value >> 8) & 0xFF00FF;␊ |
| 41 | ␉␉␉srcrb = pixel(blendThis, sx, sy).value & 0xFF00FF;␊ |
| 42 | ␉␉␉srcag = (pixel(blendThis, sx, sy).value >> 8) & 0xFF00FF;␊ |
| 43 | ␉␉␉drb = srcrb - dstrb;␊ |
| 44 | ␉␉␉dag = srcag - dstag;␊ |
| 45 | ␉␉␉drb *= alpha; dag *= alpha;␊ |
| 46 | ␉␉␉drb >>= 8; dag >>= 8;␊ |
| 47 | ␉␉␉rb = (drb + dstrb) & 0x00FF00FF;␊ |
| 48 | ␉␉␉ag = ((dag + dstag) << 8) & 0xFF00FF00;␊ |
| 49 | ␉␉␉pixel(blendInto, dx, dy).value = (rb | ag);␊ |
| 50 | ␉␉}␊ |
| 51 | ␉}␊ |
| 52 | }␊ |
| 53 | ␊ |
| 54 | position_t centeredIn( const pixmap_t *background, const pixmap_t *toCenter ) {␊ |
| 55 | ␉position_t centered;␊ |
| 56 | ␉centered.x = ( background->width - toCenter->width ) / 2;␊ |
| 57 | ␉centered.y = ( background->height - toCenter->height ) / 2;␊ |
| 58 | ␉return centered;␊ |
| 59 | }␊ |
| 60 | ␊ |
| 61 | position_t centeredAt( const pixmap_t *pixmap, const position_t center ) {␊ |
| 62 | ␉position_t topleft;␊ |
| 63 | ␉topleft.x = center.x - (pixmap->width / 2);␊ |
| 64 | ␉topleft.y = center.y - (pixmap->height / 2);␊ |
| 65 | ␉return topleft;␊ |
| 66 | }␊ |
| 67 | ␊ |
| 68 | position_t pos(const uint16_t x, const uint16_t y) { position_t p; p.x = x; p.y = y; return p; }␊ |
| 69 | ␊ |
| 70 | void flipRB(pixmap_t *p)␊ |
| 71 | {␊ |
| 72 | ␉//if(testForQemu()) return;␊ |
| 73 | ␉␊ |
| 74 | ␉uint32_t x;␊ |
| 75 | ␉register uint8_t tempB;␊ |
| 76 | ␉for (x = 0; x < (p->height) * (p->width) ; x++) {␊ |
| 77 | ␉␉tempB = (p->pixels[x]).ch.b;␊ |
| 78 | ␉␉(p->pixels[x]).ch.b = (p->pixels[x]).ch.r;␊ |
| 79 | ␉␉(p->pixels[x]).ch.r = tempB;␊ |
| 80 | ␉}␊ |
| 81 | }␊ |
| 82 | |
