diff options
Diffstat (limited to 'src/mesa/drivers/dri')
| -rw-r--r-- | src/mesa/drivers/dri/i915/i915_fragprog.c | 98 |
1 files changed, 63 insertions, 35 deletions
diff --git a/src/mesa/drivers/dri/i915/i915_fragprog.c b/src/mesa/drivers/dri/i915/i915_fragprog.c index cbac07cde1..b475fb632f 100644 --- a/src/mesa/drivers/dri/i915/i915_fragprog.c +++ b/src/mesa/drivers/dri/i915/i915_fragprog.c @@ -48,7 +48,7 @@ static const GLfloat sin_quad_constants[2][4] = { 2.0, -1.0, .5, - 0.0 + .75 }, { 4.0, @@ -375,52 +375,80 @@ upload_program(struct i915_fragment_program *p) case OPCODE_COS: src0 = src_vector(p, &inst->SrcReg[0], program); tmp = i915_get_utemp(p); + consts0 = i915_emit_const4fv(p, sin_quad_constants[0]); + consts1 = i915_emit_const4fv(p, sin_quad_constants[1]); + /* Reduce range from repeating about [-pi,pi] to [-1,1] */ i915_emit_arith(p, - A0_MUL, + A0_MAD, tmp, A0_DEST_CHANNEL_X, 0, - src0, i915_emit_const1f(p, 1.0 / (M_PI)), 0); + src0, + swizzle(consts1, Z, ZERO, ZERO, ZERO), /* 1/(2pi) */ + swizzle(consts0, W, ZERO, ZERO, ZERO)); /* .75 */ - i915_emit_arith(p, A0_MOD, tmp, A0_DEST_CHANNEL_X, 0, tmp, 0, 0); + i915_emit_arith(p, A0_FRC, tmp, A0_DEST_CHANNEL_X, 0, tmp, 0, 0); - /* By choosing different taylor constants, could get rid of this mul: - */ - i915_emit_arith(p, - A0_MUL, - tmp, A0_DEST_CHANNEL_X, 0, - tmp, i915_emit_const1f(p, (M_PI)), 0); + i915_emit_arith(p, + A0_MAD, + tmp, A0_DEST_CHANNEL_X, 0, + tmp, + swizzle(consts0, X, ZERO, ZERO, ZERO), /* 2 */ + swizzle(consts0, Y, ZERO, ZERO, ZERO)); /* -1 */ - /* - * t0.xy = MUL x.xx11, x.x1111 ; x^2, x, 1, 1 - * t0 = MUL t0.xyxy t0.xx11 ; x^4, x^3, x^2, 1 - * t0 = MUL t0.xxz1 t0.z111 ; x^6 x^4 x^2 1 - * result = DP4 t0, cos_constants - */ - i915_emit_arith(p, - A0_MUL, - tmp, A0_DEST_CHANNEL_XY, 0, - swizzle(tmp, X, X, ONE, ONE), - swizzle(tmp, X, ONE, ONE, ONE), 0); + /* Compute COS with the same calculation used for SIN, but a + * different source range has been mapped to [-1,1] this time. + */ - i915_emit_arith(p, - A0_MUL, - tmp, A0_DEST_CHANNEL_XYZ, 0, - swizzle(tmp, X, Y, X, ONE), - swizzle(tmp, X, X, ONE, ONE), 0); + /* tmp.y = abs(tmp.x); {x, abs(x), 0, 0} */ + i915_emit_arith(p, + A0_MAX, + tmp, A0_DEST_CHANNEL_Y, 0, + swizzle(tmp, ZERO, X, ZERO, ZERO), + negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0), + 0); - i915_emit_arith(p, - A0_MUL, - tmp, A0_DEST_CHANNEL_XYZ, 0, - swizzle(tmp, X, X, Z, ONE), - swizzle(tmp, Z, ONE, ONE, ONE), 0); + /* tmp.y = tmp.y * tmp.x; {x, x * abs(x), 0, 0} */ + i915_emit_arith(p, + A0_MUL, + tmp, A0_DEST_CHANNEL_Y, 0, + swizzle(tmp, ZERO, X, ZERO, ZERO), + tmp, + 0); + /* tmp.x = tmp.xy DP sin_quad_constants[2].xy */ i915_emit_arith(p, - A0_DP4, + A0_DP3, + tmp, A0_DEST_CHANNEL_X, 0, + tmp, + swizzle(consts1, X, Y, ZERO, ZERO), + 0); + + /* tmp.x now contains a first approximation (y). Now, weight it + * against tmp.y**2 to get closer. + */ + i915_emit_arith(p, + A0_MAX, + tmp, A0_DEST_CHANNEL_Y, 0, + swizzle(tmp, ZERO, X, ZERO, ZERO), + negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0), + 0); + + /* tmp.y = tmp.x * tmp.y - tmp.x; {y, y * abs(y) - y, 0, 0} */ + i915_emit_arith(p, + A0_MAD, + tmp, A0_DEST_CHANNEL_Y, 0, + swizzle(tmp, ZERO, X, ZERO, ZERO), + swizzle(tmp, ZERO, Y, ZERO, ZERO), + negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0)); + + /* result = .2225 * tmp.y + tmp.x =.2225(y * abs(y) - y) + y= */ + i915_emit_arith(p, + A0_MAD, get_result_vector(p, inst), get_result_flags(inst), 0, - swizzle(tmp, ONE, Z, Y, X), - i915_emit_const4fv(p, cos_constants), 0); - + swizzle(consts1, W, W, W, W), + swizzle(tmp, Y, Y, Y, Y), + swizzle(tmp, X, X, X, X)); break; case OPCODE_DP3: |