Files
Upsilon/apps/graph/graph/graph_view.cpp
Émilie Feral beaedc8888 [apps/graph] Redefinition of active function
Change-Id: I23e83a1107daf85bdf99c7b100d8bca6d724c919
2016-11-23 12:17:31 +01:00

288 lines
9.2 KiB
C++

#include "graph_view.h"
#include <assert.h>
namespace Graph {
constexpr KDColor kAxisColor = KDColor::RGB24(0x000000);
constexpr KDColor kMainGridColor = KDColor::RGB24(0xCCCCCC);
constexpr KDColor kSecondaryGridColor = KDColor::RGB24(0xEEEEEE);
constexpr int kNumberOfMainGridLines = 5;
constexpr int kNumberOfSecondaryGridLines = 4;
constexpr KDCoordinate GraphView::k_stampSize;
constexpr uint8_t GraphView::k_mask[k_stampSize*k_stampSize];
GraphView::GraphView(FunctionStore * functionStore) :
#if GRAPH_VIEW_IS_TILED
TiledView(),
#else
View(),
#endif
m_cursorView(CursorView()),
m_cursorPosition(KDPointZero),
m_xMin(-2.0f),
m_xMax(2.0f),
m_yMin(-2.0f),
m_yMax(2.0f),
m_functionStore(functionStore),
m_evaluateContext(nullptr)
{
}
int GraphView::numberOfSubviews() const {
return 1;
};
View * GraphView::subviewAtIndex(int index) {
return &m_cursorView;
}
void GraphView::setContext(Context * context) {
m_evaluateContext = (EvaluateContext *)context;
}
Context * GraphView::context() const {
return m_evaluateContext;
}
void GraphView::moveCursorRight() {
KDPoint offset = KDPoint(2,0);
m_cursorPosition = m_cursorPosition.translatedBy(offset);
layoutSubviews();
}
void GraphView::layoutSubviews() {
KDRect cursorFrame(m_cursorPosition, 10, 10);
m_cursorView.setFrame(cursorFrame);
}
#if GRAPH_VIEW_IS_TILED
KDColor * GraphView::tile() const {
return (KDColor *)m_tile;
}
KDSize GraphView::tileSize() const {
return {kTileWidth, kTileHeight};
}
void GraphView::drawTile(KDContext * ctx, KDRect rect) const {
#else
void GraphView::drawRect(KDContext * ctx, KDRect rect) const {
#endif
ctx->fillRect(rect, KDColorWhite);
drawGrid(ctx, rect);
drawAxes(ctx, rect);
drawFunction(ctx, rect);
/*
constexpr int maskLength = 3;
uint8_t mask[maskLength] = {
#if 1
0x10, 0x70, 0xE0,
#else
0x00, 0x30, 0x73, 0x30, 0x00,
0x30, 0xfb, 0xff, 0xfb, 0x30,
0x73, 0xff, 0xff, 0xff, 0x73,
0x30, 0xfb, 0xff, 0xfb, 0x30,
0x00, 0x30, 0x73, 0x30, 0x00
#endif
};
KDColor red = KDColorRed;
KDBlitRect(rect, &red, 1, mask, maskLength);
*/
}
void GraphView::drawLine(KDContext * ctx, KDRect rect, Axis axis, float coordinate, KDColor color, KDCoordinate thickness) const {
KDRect lineRect = KDRectZero;
switch(axis) {
case Axis::Horizontal:
lineRect = KDRect(
rect.x(), floatToPixel(Axis::Vertical, coordinate),
rect.width(), thickness
);
break;
case Axis::Vertical:
lineRect = KDRect(
floatToPixel(Axis::Horizontal, coordinate), rect.y(),
thickness, rect.height()
);
break;
}
ctx->fillRect(lineRect, color);
}
void GraphView::drawAxes(KDContext * ctx, KDRect rect) const {
drawLine(ctx, rect, Axis::Horizontal, 0.0f, kAxisColor, 2);
drawLine(ctx, rect, Axis::Vertical, 0.0f, kAxisColor, 2);
}
void GraphView::drawGridLines(KDContext * ctx, KDRect rect, Axis axis, int count, KDColor color) const {
float range = max(axis)-min(axis);
float step = range/count;
float start = step*((int)(min(axis)/step));
for (int i=0; i<count; i++) {
Axis otherAxis = (axis == Axis::Horizontal) ? Axis::Vertical : Axis::Horizontal;
drawLine(ctx, rect, otherAxis, start+i*step, color);
}
}
void GraphView::drawGrid(KDContext * ctx, KDRect rect) const {
drawGridLines(ctx, rect, Axis::Horizontal, kNumberOfMainGridLines*kNumberOfSecondaryGridLines, kSecondaryGridColor);
drawGridLines(ctx, rect, Axis::Vertical, kNumberOfMainGridLines*kNumberOfSecondaryGridLines, kSecondaryGridColor);
drawGridLines(ctx, rect, Axis::Horizontal, kNumberOfMainGridLines, kMainGridColor);
drawGridLines(ctx, rect, Axis::Vertical, kNumberOfMainGridLines, kMainGridColor);
}
float GraphView::min(Axis axis) const {
assert(axis == Axis::Horizontal || axis == Axis::Vertical);
return (axis == Axis::Horizontal ? m_xMin : m_yMin);
}
float GraphView::max(Axis axis) const {
assert(axis == Axis::Horizontal || axis == Axis::Vertical);
return (axis == Axis::Horizontal ? m_xMax : m_yMax);
}
KDCoordinate GraphView::pixelLength(Axis axis) const {
assert(axis == Axis::Horizontal || axis == Axis::Vertical);
return (axis == Axis::Horizontal ? m_frame.width() : m_frame.height());
}
float GraphView::pixelToFloat(Axis axis, KDCoordinate p) const {
KDCoordinate pixels = axis == Axis::Horizontal ? p : pixelLength(axis)-p;
return min(axis) + pixels*(max(axis)-min(axis))/pixelLength(axis);
}
KDCoordinate GraphView::floatToPixel(Axis axis, float f) const {
float fraction = (f-min(axis))/(max(axis)-min(axis));
fraction = axis == Axis::Horizontal ? fraction : 1.0f - fraction;
/* KDCoordinate does not support as big number as float. We thus cap the
* fraction before casting. */
fraction = fraction > 2 ? 2.0f : fraction;
fraction = fraction < -1 ? -1.0f : fraction;
return pixelLength(axis)*fraction;
}
void GraphView::drawFunction(KDContext * ctx, KDRect rect) const {
KDColor workingBuffer[k_stampSize*k_stampSize];
for (int i=0; i<m_functionStore->numberOfActiveFunctions(); i++) {
Function * f = m_functionStore->activeFunctionAtIndex(i);
float y = 0.0f;
float x = 0.0f;
for (KDCoordinate px = rect.x()-k_stampSize; px<rect.right(); px++) {
float previousX = x;
x = pixelToFloat(Axis::Horizontal, px);
float previousY = y;
y = f->evaluateAtAbscissa(x, m_evaluateContext);
KDCoordinate py = floatToPixel(Axis::Vertical, y);
stampAtLocation(px, py, f->color(), ctx, workingBuffer);
if (px > rect.x()-k_stampSize) {
jointDots(previousX, previousY, x, y, f, k_maxNumberOfIterations, ctx, workingBuffer);
}
}
}
}
void GraphView::stampAtLocation(KDCoordinate px, KDCoordinate py, KDColor color, KDContext * ctx, KDColor * workingBuffer) const {
// We avoid drawing when no part of the stamp is visible
if (px < -k_stampSize || px > pixelLength(Axis::Horizontal)+k_stampSize || py < -k_stampSize || py > pixelLength(Axis::Vertical)+k_stampSize) {
return;
}
KDRect stampRect(px-k_stampSize/2, py-k_stampSize/2, k_stampSize, k_stampSize);
ctx->blendRectWithMask(stampRect, color, k_mask, workingBuffer);
}
void GraphView::jointDots(float x, float y, float u, float v, Function * function, int maxNumberOfRecursion, KDContext * ctx, KDColor * workingBuffer) const {
KDCoordinate px = floatToPixel(Axis::Horizontal, x);
KDCoordinate pu = floatToPixel(Axis::Horizontal, u);
KDCoordinate py = floatToPixel(Axis::Vertical, y);
KDCoordinate pv = floatToPixel(Axis::Vertical, v);
if (py - k_stampSize/2 < pv && pv < py + k_stampSize/2) {
// the dots are already joined
return;
}
float middleX = (x + u)/2;
float middleY = function->evaluateAtAbscissa(middleX, m_evaluateContext);
KDCoordinate pMiddleX = floatToPixel(Axis::Horizontal, middleX);
KDCoordinate pMiddleY = floatToPixel(Axis::Vertical, middleY);
if ((y < middleY && middleY < v) || (v < middleY && middleY < u)) {
/* As the middle dot is vertically between the two dots, we assume that we
* can draw a 'straight' line between the two */
straightJoinDots(px, py, pu, pv, function, ctx, workingBuffer);
return;
}
if (maxNumberOfRecursion > 0) {
stampAtLocation(pMiddleX, pMiddleY, function->color(), ctx, workingBuffer);
jointDots(x, y, middleX, middleY, function, maxNumberOfRecursion-1, ctx, workingBuffer);
jointDots(middleX, middleY, u, v, function, maxNumberOfRecursion-1, ctx, workingBuffer);
}
}
void GraphView::straightJoinDots(KDCoordinate px, KDCoordinate py, KDCoordinate pu, KDCoordinate pv, Function * function, KDContext * ctx, KDColor * workingBuffer) const {
if (py < pv) {
KDCoordinate pm = px;
KDCoordinate pVerticalMiddle = (py + pv)/2;
for (KDCoordinate pn = py; pn < pv; pn++) {
if (pn == pVerticalMiddle) {
pm = pu;
}
stampAtLocation(pm, pn, function->color(), ctx, workingBuffer);
}
return;
}
straightJoinDots(pu, pv, px, py, function, ctx, workingBuffer);
}
#if 0
void GraphView::drawFunction(KDRect rect) const {
/* Naive algorithm: iterate on pixels horizontally
* Actually, this is kinda optimal. If two consecutive pixels don't touch
* (i.e. they have a y-difference greater than 1), just draw a vertical line.
* This may seem stupid but is kinda good actually. */
KDCoordinate previousPixelY;
KDCoordinate pixelX;
KDColor curveColor = KDColorRGB(0xFF, 0, 0);
#define ANTI_ALIASING
#ifdef ANTI_ALIASING
KDColor antiAliasingColor = KDColorRGB(0, 0xFF, 0);
#endif
for (pixelX=rect.x; pixelX<(rect.x+rect.width); pixelX++) {
float x = pixelToFloat(Axis::Horizontal, pixelX);
float y = (x-1)*(x+1)*x;
KDCoordinate pixelY = floatToPixel(Axis::Vertical, y);
KDRect r;
r.x = pixelX;
if (pixelY < previousPixelY) {
r.y = pixelY;
r.height = previousPixelY-pixelY;
KDPoint p;
p.x = pixelX-1;
p.y = previousPixelY+3;
KDSetPixel(p, KDColorRGB(0x00, 0xFF, 0x00));
p.x = pixelX;
p.y = pixelY-1;
KDSetPixel(p, KDColorRGB(0x00, 0xFF, 0x00));
} else {
r.y = previousPixelY;
r.height = pixelY - previousPixelY;
}
if (r.height == 0) {
r.height = 1;
}
r.width = 1;
r.width += 2;
r.height += 2;
//KDFillRectWithPattern(r, antialiasedDot);
KDFillRect(r, KDColorRGB(0xFF, 0, 0));
previousPixelY = pixelY;
}
}
#endif
}