Merge branch 'release/experimental/1.0.29-1_experimental1'experimental/1.0.29-1_experimental1

1 files changed, 177 insertions, 0 deletions

diff --git a/backend/genesys/motor.h b/backend/genesys/motor.h
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+/* sane - Scanner Access Now Easy.
+
+   Copyright (C) 2019 Povilas Kanapickas <povilas@radix.lt>
+
+   This file is part of the SANE package.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+   MA 02111-1307, USA.
+
+   As a special exception, the authors of SANE give permission for
+   additional uses of the libraries contained in this release of SANE.
+
+   The exception is that, if you link a SANE library with other files
+   to produce an executable, this does not by itself cause the
+   resulting executable to be covered by the GNU General Public
+   License.  Your use of that executable is in no way restricted on
+   account of linking the SANE library code into it.
+
+   This exception does not, however, invalidate any other reasons why
+   the executable file might be covered by the GNU General Public
+   License.
+
+   If you submit changes to SANE to the maintainers to be included in
+   a subsequent release, you agree by submitting the changes that
+   those changes may be distributed with this exception intact.
+
+   If you write modifications of your own for SANE, it is your choice
+   whether to permit this exception to apply to your modifications.
+   If you do not wish that, delete this exception notice.
+*/
+
+#ifndef BACKEND_GENESYS_MOTOR_H
+#define BACKEND_GENESYS_MOTOR_H
+
+#include <cstdint>
+#include <vector>
+#include "enums.h"
+
+namespace genesys {
+
+/*  Describes a motor acceleration curve.
+
+    Definitions:
+        v - speed in steps per pixeltime
+        w - speed in pixel times per step. w = 1 / v
+        a - acceleration in steps per pixeltime squared
+        s - distance travelled in steps
+        t - time in pixeltime
+
+    The physical mode defines the curve in physical quantities. We asssume that the scanner head
+    accelerates from standstill to the target speed uniformly. Then:
+
+    v(t) = v(0) + a * t                                                                         (2)
+
+    Where `a` is acceleration, `t` is time. Also we can calculate the travelled distance `s`:
+
+    s(t) = v(0) * t + a * t^2 / 2                                                               (3)
+
+    The actual motor slope is defined as the duration of each motor step. That means we need to
+    define speed in terms of travelled distance.
+
+    Solving (3) for `t` gives:
+
+           sqrt( v(0)^2 + 2 * a * s ) - v(0)
+    t(s) = ---------------------------------                                                    (4)
+                          a
+
+    Combining (4) and (2) will yield:
+
+    v(s) = sqrt( v(0)^2 + 2 * a * s )                                                           (5)
+
+    The data in the slope struct MotorSlope corresponds to the above in the following way:
+
+    maximum_start_speed is `w(0) = 1/v(0)`
+
+    maximum_speed is defines maximum speed which should not be exceeded
+
+    minimum_steps is not used
+
+    g is `a`
+
+    Given the start and target speeds on a known motor curve, `a` can be computed as follows:
+
+        v(t1)^2 - v(t0)^2
+    a = -----------------                                                                       (6)
+               2 * s
+
+    Here `v(t0)` and `v(t1)` are the start and target speeds and `s` is the number of step required
+    to reach the target speeds.
+*/
+struct MotorSlope
+{
+    // initial speed in pixeltime per step
+    unsigned initial_speed_w = 0;
+
+    // max speed in pixeltime per step
+    unsigned max_speed_w = 0;
+
+    // maximum number of steps in the table
+    unsigned max_step_count;
+
+    // acceleration in steps per pixeltime squared.
+    float acceleration = 0;
+
+    unsigned get_table_step_shifted(unsigned step, StepType step_type) const;
+
+    static MotorSlope create_from_steps(unsigned initial_w, unsigned max_w,
+                                        unsigned steps);
+};
+
+struct MotorSlopeTable
+{
+    std::vector<std::uint16_t> table;
+    unsigned steps_count = 0;
+    unsigned pixeltime_sum = 0;
+
+    void slice_steps(unsigned count);
+};
+
+unsigned get_slope_table_max_size(AsicType asic_type);
+
+MotorSlopeTable create_slope_table(const MotorSlope& slope, unsigned target_speed_w,
+                                   StepType step_type, unsigned steps_alignment,
+                                   unsigned min_size, unsigned max_size);
+
+std::ostream& operator<<(std::ostream& out, const MotorSlope& slope);
+
+
+struct Genesys_Motor
+{
+    Genesys_Motor() = default;
+
+    // id of the motor description
+    MotorId id = MotorId::UNKNOWN;
+    // motor base steps. Unit: 1/inch
+    int base_ydpi = 0;
+    // maximum resolution in y-direction. Unit: 1/inch
+    int optical_ydpi = 0;
+    // slopes to derive individual slopes from
+    std::vector<MotorSlope> slopes;
+
+    MotorSlope& get_slope(StepType step_type)
+    {
+        return slopes[static_cast<unsigned>(step_type)];
+    }
+
+    const MotorSlope& get_slope(StepType step_type) const
+    {
+        return slopes[static_cast<unsigned>(step_type)];
+    }
+
+    StepType max_step_type() const
+    {
+        if (slopes.empty()) {
+            throw std::runtime_error("Slopes table is empty");
+        }
+        return static_cast<StepType>(slopes.size() - 1);
+    }
+};
+
+std::ostream& operator<<(std::ostream& out, const Genesys_Motor& motor);
+
+} // namespace genesys
+
+#endif // BACKEND_GENESYS_MOTOR_H