Update StraightLineView.cpp

This commit is contained in:
xixu-me committed 2024-09-19 15:15:47 +08:00
1 parent 371a070797
commit 8b1db0b997
1 file changed
+126 -47
+126 -47
View File
@@ -92,7 +92,8 @@ void CStraightLineView::OnDraw(CDC *pDC) {
memDC.TextOutW(10, m_rect.Height() / 2, _T("y"));
// 调用Bresenham算法绘制直线
BresenhamLine(&memDC);
// BresenhamLine(&memDC);
WuLine(&memDC);
// 设置显示设备上下文的映射模式和视口
pDC->SetMapMode(MM_ANISOTROPIC);
@@ -155,13 +156,136 @@ void CStraightLineView::BresenhamLine(CDC *pDC) {
int totalSteps = max(abs(dx), abs(dy));
// 定义颜色插值函数
auto interpolateColor = [](COLORREF start, COLORREF end, DOUBLE factor) -> COLORREF {
auto interpolateColor = [](COLORREF start, COLORREF end, double factor) -> COLORREF {
BYTE r = static_cast<BYTE>(GetRValue(start) + factor * (GetRValue(end) - GetRValue(start)));
BYTE g = static_cast<BYTE>(GetGValue(start) + factor * (GetGValue(end) - GetGValue(start)));
BYTE b = static_cast<BYTE>(GetBValue(start) + factor * (GetBValue(end) - GetBValue(start)));
return RGB(r, g, b);
};
// 处理垂直线的情况
if (ptOrigin.x == ptEnd.x) {
if (ptOrigin.y > ptEnd.y) {
ptTemp = ptOrigin;
ptOrigin = ptEnd;
ptEnd = ptTemp;
}
for (int y = ptOrigin.y; y <= ptEnd.y; y++) {
double factor = (double)(y - ptOrigin.y) / totalSteps;
COLORREF color = interpolateColor(startColor, endColor, factor);
pDC->SetPixelV(ptOrigin.x, y, color);
}
}
else {
// 计算斜率
DOUBLE k = (DOUBLE)dy / dx;
DOUBLE d;
// 处理斜率在[0, 1]之间的情况
if (k >= 0 && k <= 1) {
d = 0.5 - k;
if (ptOrigin.x > ptEnd.x) {
ptTemp = ptOrigin;
ptOrigin = ptEnd;
ptEnd = ptTemp;
}
for (ptTemp = ptOrigin; ptTemp.x <= ptEnd.x; ptTemp.x++) {
double factor = (double)(ptTemp.x - ptOrigin.x) / totalSteps;
COLORREF color = interpolateColor(startColor, endColor, factor);
pDC->SetPixelV(ptTemp.x, ptTemp.y, color);
if (d < 0) {
d += 1 - k;
ptTemp.y++;
}
else {
d -= k;
}
}
}
// 处理斜率大于1的情况
else if (k > 1) {
d = 0.5 - 1 / k;
if (ptOrigin.y > ptEnd.y) {
ptTemp = ptOrigin;
ptOrigin = ptEnd;
ptEnd = ptTemp;
}
for (ptTemp = ptOrigin; ptTemp.y <= ptEnd.y; ptTemp.y++) {
double factor = (double)(ptTemp.y - ptOrigin.y) / totalSteps;
COLORREF color = interpolateColor(startColor, endColor, factor);
pDC->SetPixelV(ptTemp.x, ptTemp.y, color);
if (d < 0) {
d += 1 - 1 / k;
ptTemp.x++;
}
else {
d -= 1 / k;
}
}
}
// 处理斜率在[-1, 0]之间的情况
else if (k < 0 && k >= -1) {
d = 0.5 + k;
if (ptOrigin.x > ptEnd.x) {
ptTemp = ptOrigin;
ptOrigin = ptEnd;
ptEnd = ptTemp;
}
for (ptTemp = ptOrigin; ptTemp.x <= ptEnd.x; ptTemp.x++) {
double factor = (double)(ptTemp.x - ptOrigin.x) / totalSteps;
COLORREF color = interpolateColor(startColor, endColor, factor);
pDC->SetPixelV(ptTemp.x, ptTemp.y, color);
if (d < 0) {
d += 1 + k;
ptTemp.y--;
}
else {
d += k;
}
}
}
// 处理斜率小于-1的情况
else {
d = 0.5 + 1 / k;
if (ptOrigin.y < ptEnd.y) {
ptTemp = ptOrigin;
ptOrigin = ptEnd;
ptEnd = ptTemp;
}
for (ptTemp = ptOrigin; ptTemp.y >= ptEnd.y; ptTemp.y--) {
double factor = (double)(ptOrigin.y - ptTemp.y) / totalSteps;
COLORREF color = interpolateColor(startColor, endColor, factor);
pDC->SetPixelV(ptTemp.x, ptTemp.y, color);
if (d < 0) {
d += 1 + 1 / k;
ptTemp.x++;
}
else {
d += 1 / k;
}
}
}
}
}
void CStraightLineView::WuLine(CDC *pDC) {
// 定义起始颜色和结束颜色
COLORREF startColor = RGB(0, 82, 217);
COLORREF endColor = RGB(236, 189, 101);
// 获取起点和终点坐标
CPoint ptOrigin = m_ptOrigin, ptEnd = m_ptEnd, ptTemp;
LONG dx = ptEnd.x - ptOrigin.x, dy = ptEnd.y - ptOrigin.y;
int totalSteps = max(abs(dx), abs(dy));
// 定义颜色插值函数
// auto interpolateColor = [](COLORREF start, COLORREF end, DOUBLE factor) -> COLORREF {
// BYTE r = static_cast<BYTE>(GetRValue(start) + factor * (GetRValue(end) - GetRValue(start)));
// BYTE g = static_cast<BYTE>(GetGValue(start) + factor * (GetGValue(end) - GetGValue(start)));
// BYTE b = static_cast<BYTE>(GetBValue(start) + factor * (GetBValue(end) - GetBValue(start)));
// return RGB(r, g, b);
// };
// 处理垂直线的情况
if (ptOrigin.x == ptEnd.x) {
if (ptOrigin.y > ptEnd.y) {
@@ -170,9 +294,6 @@ void CStraightLineView::BresenhamLine(CDC *pDC) {
ptEnd = ptTemp;
}
for (int y = ptOrigin.y; y < ptEnd.y; y++) {
// DOUBLE factor = (DOUBLE)(y - ptOrigin.y) / totalSteps;
// COLORREF color = interpolateColor(startColor, endColor, factor);
// pDC->SetPixelV(ptOrigin.x, y, color);
pDC->SetPixelV(ptOrigin.x, y, RGB(0, 0, 0));
}
}
@@ -189,20 +310,10 @@ void CStraightLineView::BresenhamLine(CDC *pDC) {
ptOrigin = ptEnd;
ptEnd = ptTemp;
}
// d = 0.5 - k;
for (ptTemp = ptOrigin, e = k; ptTemp.x < ptEnd.x; ptTemp.x++) {
// DOUBLE factor = (DOUBLE)(ptTemp.x - ptOrigin.x) / totalSteps;
// COLORREF color = interpolateColor(startColor, endColor, factor);
pDC->SetPixelV(ptTemp.x, ptTemp.y, RGB(e * 255, e * 255, e * 255));
pDC->SetPixelV(ptTemp.x, ptTemp.y + 1, RGB((1.0 - e) * 255, (1.0 - e) * 255, (1.0 - e) * 255));
e += k;
// if (d < 0) {
// d += 1 - k;
// ptTemp.y++;
// }
// else {
// d -= k;
// }
if (e >= 1.0) {
ptTemp.y++;
e--;
@@ -218,19 +329,9 @@ void CStraightLineView::BresenhamLine(CDC *pDC) {
}
// d = 0.5 - 1 / k;
for (ptTemp = ptOrigin, e = 1 / k; ptTemp.y < ptEnd.y; ptTemp.y++) {
// DOUBLE factor = (DOUBLE)(ptOrigin.y - ptTemp.y) / totalSteps;
// COLORREF color = interpolateColor(startColor, endColor, factor);
// pDC->SetPixelV(ptTemp.x, ptTemp.y, color);
pDC->SetPixelV(ptTemp.x, ptTemp.y, RGB(e * 255, e * 255, e * 255));
pDC->SetPixelV(ptTemp.x + 1, ptTemp.y, RGB((1.0 - e) * 255, (1.0 - e) * 255, (1.0 - e) * 255));
e += 1 / k;
// if (d < 0) {
// d += 1 - 1 / k;
// ptTemp.x++;
// }
// else {
// d -= 1 / k;
// }
if (e >= 1.0) {
ptTemp.x++;
e--;
@@ -244,21 +345,10 @@ void CStraightLineView::BresenhamLine(CDC *pDC) {
ptOrigin = ptEnd;
ptEnd = ptTemp;
}
// d = 0.5 + k;
for (ptTemp = ptOrigin, e = -k; ptTemp.x < ptEnd.x; ptTemp.x++) {
// DOUBLE factor = (DOUBLE)(ptTemp.x - ptOrigin.x) / totalSteps;
// COLORREF color = interpolateColor(startColor, endColor, factor);
// pDC->SetPixelV(ptTemp.x, ptTemp.y, color);
pDC->SetPixelV(ptTemp.x, ptTemp.y, RGB(e * 255, e * 255, e * 255));
pDC->SetPixelV(ptTemp.x, ptTemp.y - 1, RGB((1 - e) * 255, (1 - e) * 255, (1 - e) * 255));
e -= k;
// if (d < 0) {
// d += 1 + k;
// ptTemp.y--;
// }
// else {
// d += k;
// }
if (e >= 1.0) {
ptTemp.y--;
e--;
@@ -272,21 +362,10 @@ void CStraightLineView::BresenhamLine(CDC *pDC) {
ptOrigin = ptEnd;
ptEnd = ptTemp;
}
// d = 0.5 + 1 / k;
for (ptTemp = ptOrigin, e = -1 / k; ptTemp.y > ptEnd.y; ptTemp.y--) {
// DOUBLE factor = (DOUBLE)(ptOrigin.y - ptTemp.y) / totalSteps;
// COLORREF color = interpolateColor(startColor, endColor, factor);
// pDC->SetPixelV(ptTemp.x, ptTemp.y, color);
pDC->SetPixelV(ptTemp.x, ptTemp.y, RGB(e * 255, e * 255, e * 255));
pDC->SetPixelV(ptTemp.x + 1, ptTemp.y, RGB((1 - e) * 255, (1 - e) * 255, (1 - e) * 255));
e -= 1 / k;
// if (d < 0) {
// d += 1 + 1 / k;
// ptTemp.x++;
// }
// else {
// d += 1 / k;
// }
if (e >= 1.0) {
ptTemp.x++;
e--;