diff options
Diffstat (limited to 'src/mesa/drivers/dri/i915/intel_rotate.c')
| -rw-r--r-- | src/mesa/drivers/dri/i915/intel_rotate.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/src/mesa/drivers/dri/i915/intel_rotate.c b/src/mesa/drivers/dri/i915/intel_rotate.c new file mode 100644 index 00000000000..a77640ee54d --- /dev/null +++ b/src/mesa/drivers/dri/i915/intel_rotate.c @@ -0,0 +1,221 @@ + +/** + * Routines for simple 2D->2D transformations for rotated, flipped screens. + * + * XXX This code is not intel-specific. Move it into a common/utility + * someday. + */ + +#include "intel_rotate.h" + +#define MIN2(A, B) ( ((A) < (B)) ? (A) : (B) ) + +#define ABS(A) ( ((A) < 0) ? -(A) : (A) ) + + +void +matrix23Set(struct matrix23 *m, + int m00, int m01, int m02, + int m10, int m11, int m12) +{ + m->m00 = m00; m->m01 = m01; m->m02 = m02; + m->m10 = m10; m->m11 = m11; m->m12 = m12; +} + + +/* + * Transform (x,y) coordinate by the given matrix. + */ +void +matrix23TransformCoordf(const struct matrix23 *m, float *x, float *y) +{ + const float x0 = *x; + const float y0 = *y; + + *x = m->m00 * x0 + m->m01 * y0 + m->m02; + *y = m->m10 * x0 + m->m11 * y0 + m->m12; +} + + +void +matrix23TransformCoordi(const struct matrix23 *m, int *x, int *y) +{ + const int x0 = *x; + const int y0 = *y; + + *x = m->m00 * x0 + m->m01 * y0 + m->m02; + *y = m->m10 * x0 + m->m11 * y0 + m->m12; +} + + +/* + * Transform a width and height by the given matrix. + * XXX this could be optimized quite a bit. + */ +void +matrix23TransformDistance(const struct matrix23 *m, int *xDist, int *yDist) +{ + int x0 = 0, y0 = 0; + int x1 = *xDist, y1 = 0; + int x2 = 0, y2 = *yDist; + matrix23TransformCoordi(m, &x0, &y0); + matrix23TransformCoordi(m, &x1, &y1); + matrix23TransformCoordi(m, &x2, &y2); + + *xDist = (x1 - x0) + (x2 - x0); + *yDist = (y1 - y0) + (y2 - y0); + + if (*xDist < 0) + *xDist = -*xDist; + if (*yDist < 0) + *yDist = -*yDist; +} + + +/** + * Transform the rect defined by (x, y, w, h) by m. + */ +void +matrix23TransformRect(const struct matrix23 *m, int *x, int *y, int *w, int *h) +{ + int x0 = *x, y0 = *y; + int x1 = *x + *w, y1 = *y; + int x2 = *x + *w, y2 = *y + *h; + int x3 = *x, y3 = *y + *h; + matrix23TransformCoordi(m, &x0, &y0); + matrix23TransformCoordi(m, &x1, &y1); + matrix23TransformCoordi(m, &x2, &y2); + matrix23TransformCoordi(m, &x3, &y3); + *w = ABS(x1 - x0) + ABS(x2 - x1); + /**w = ABS(*w);*/ + *h = ABS(y1 - y0) + ABS(y2 - y1); + /**h = ABS(*h);*/ + *x = MIN2(x0, x1); + *x = MIN2(*x, x2); + *y = MIN2(y0, y1); + *y = MIN2(*y, y2); +} + + +/* + * Make rotation matrix for width X height screen. + */ +void +matrix23Rotate(struct matrix23 *m, int width, int height, int angle) +{ + switch (angle) { + case 0: + matrix23Set(m, 1, 0, 0, 0, 1, 0); + break; + case 90: + matrix23Set(m, 0, 1, 0, -1, 0, width); + break; + case 180: + matrix23Set(m, -1, 0, width, 0, -1, height); + break; + case 270: + matrix23Set(m, 0, -1, height, 1, 0, 0); + break; + default: + /*abort()*/; + } +} + + +/* + * Make flip/reflection matrix for width X height screen. + */ +void +matrix23Flip(struct matrix23 *m, int width, int height, int xflip, int yflip) +{ + if (xflip) { + m->m00 = -1; m->m01 = 0; m->m02 = width - 1; + } + else { + m->m00 = 1; m->m01 = 0; m->m02 = 0; + } + if (yflip) { + m->m10 = 0; m->m11 = -1; m->m12 = height - 1; + } + else { + m->m10 = 0; m->m11 = 1; m->m12 = 0; + } +} + + +/* + * result = a * b + */ +void +matrix23Multiply(struct matrix23 *result, + const struct matrix23 *a, const struct matrix23 *b) +{ + result->m00 = a->m00 * b->m00 + a->m01 * b->m10; + result->m01 = a->m00 * b->m01 + a->m01 * b->m11; + result->m02 = a->m00 * b->m02 + a->m01 * b->m12 + a->m02; + + result->m10 = a->m10 * b->m00 + a->m11 * b->m10; + result->m11 = a->m10 * b->m01 + a->m11 * b->m11; + result->m12 = a->m10 * b->m02 + a->m11 * b->m12 + a->m12; +} + + +#if 000 + +#include <stdio.h> + +int +main(int argc, char *argv[]) +{ + int width = 500, height = 400; + int rot; + int fx = 0, fy = 0; /* flip x and/or y ? */ + int coords[4][2]; + + /* four corner coords to test with */ + coords[0][0] = 0; coords[0][1] = 0; + coords[1][0] = width-1; coords[1][1] = 0; + coords[2][0] = width-1; coords[2][1] = height-1; + coords[3][0] = 0; coords[3][1] = height-1; + + + for (rot = 0; rot < 360; rot += 90) { + struct matrix23 rotate, flip, m; + int i; + + printf("Rot %d, xFlip %d, yFlip %d:\n", rot, fx, fy); + + /* make transformation matrix 'm' */ + matrix23Rotate(&rotate, width, height, rot); + matrix23Flip(&flip, width, height, fx, fy); + matrix23Multiply(&m, &rotate, &flip); + + /* xform four coords */ + for (i = 0; i < 4; i++) { + int x = coords[i][0]; + int y = coords[i][1]; + matrix23TransformCoordi(&m, &x, &y); + printf(" %d, %d -> %d %d\n", coords[i][0], coords[i][1], x, y); + } + + /* xform width, height */ + { + int x = width; + int y = height; + matrix23TransformDistance(&m, &x, &y); + printf(" %d x %d -> %d x %d\n", width, height, x, y); + } + + /* xform rect */ + { + int x = 50, y = 10, w = 200, h = 100; + matrix23TransformRect(&m, &x, &y, &w, &h); + printf(" %d,%d %d x %d -> %d, %d %d x %d\n", 50, 10, 200, 100, + x, y, w, h); + } + + } + + return 0; +} +#endif |