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@@ -2414,7 +2414,7 @@ void ImageDrawPixelV(Image *dst, Vector2 position, Color color)
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{
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ImageDrawPixel(dst, (int)position.x, (int)position.y, color);
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}
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-
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+
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// Draw line within an image
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void ImageDrawLine(Image *dst, int startPosX, int startPosY, int endPosX, int endPosY, Color color)
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{
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@@ -2423,99 +2423,89 @@ void ImageDrawLine(Image *dst, int startPosX, int startPosY, int endPosX, int en
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// https://classic.csunplugged.org/wp-content/uploads/2014/12/Lines.pdf
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int changeInX = (endPosX - startPosX);
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- int abs_changeInX = (changeInX < 0)? -changeInX : changeInX;
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+ int absChangeInX = (changeInX < 0)? -changeInX : changeInX;
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int changeInY = (endPosY - startPosY);
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- int abs_changeInY = (changeInY < 0)? -changeInY : changeInY;
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+ int absChangeInY = (changeInY < 0)? -changeInY : changeInY;
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- int startU, startV, endU, V_step; // Substitutions, either U = X, V = Y or vice versa. See loop at end of function
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- //int endV; // This is not needed, but to aid understanding it is left in the code below.
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-
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- int A, B, P; // See linked paper above. Explained down in the main loop.
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-
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- int is_x_y_reversed = (abs_changeInY < abs_changeInX);
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+ int startU, startV, endU, stepV; // Substitutions, either U = X, V = Y or vice versa. See loop at end of function
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+ //int endV; // Not needed but left for better understanding, check code below
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+ int A, B, P; // See linked paper above, explained down in the main loop
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+ int reversedXY = (absChangeInY < absChangeInX);
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- if (is_x_y_reversed)
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+ if (reversedXY)
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{
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- A = 2*abs_changeInY;
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- B = A - 2*abs_changeInX;
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- P = A - abs_changeInX;
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+ A = 2*absChangeInY;
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+ B = A - 2*absChangeInX;
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+ P = A - absChangeInX;
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- if (changeInX > 0)
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+ if (changeInX > 0)
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{
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startU = startPosX;
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startV = startPosY;
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endU = endPosX;
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- //endV = endPosY;
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+ //endV = endPosY;
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}
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else
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{
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startU = endPosX;
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startV = endPosY;
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endU = startPosX;
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- //endV = startPosY;
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+ //endV = startPosY;
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- // since start and end are reversed:
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+ // Since start and end are reversed
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changeInX = -changeInX;
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changeInY = -changeInY;
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}
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- V_step = (changeInY < 0)? -1 : 1;
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+ stepV = (changeInY < 0)? -1 : 1;
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- ImageDrawPixel(dst, startU, startV, color); // At this point they are correctly ordered...
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+ ImageDrawPixel(dst, startU, startV, color); // At this point they are correctly ordered...
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}
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- else // all X and Y are reversed in here:
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+ else
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{
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- A = 2*abs_changeInX;
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- B = A - 2*abs_changeInY;
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- P = A - abs_changeInY;
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+ A = 2*absChangeInX;
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+ B = A - 2*absChangeInY;
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+ P = A - absChangeInY;
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if (changeInY > 0)
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{
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startU = startPosY;
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startV = startPosX;
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endU = endPosY;
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- //endV = endPosX;
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+ //endV = endPosX;
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}
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else
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{
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startU = endPosY;
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startV = endPosX;
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endU = startPosY;
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- //endV = startPosX;
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+ //endV = startPosX;
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- // since start and end are reversed:
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+ // Since start and end are reversed
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changeInX = -changeInX;
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changeInY = -changeInY;
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}
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- V_step = (changeInX < 0)? -1 : 1;
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+ stepV = (changeInX < 0)? -1 : 1;
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- ImageDrawPixel(dst, startV, startU, color); // ... but need to be reversed here. Repeated in the main loop below.
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+ ImageDrawPixel(dst, startV, startU, color); // ... but need to be reversed here. Repeated in the main loop below
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}
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- // We already drew the start point. If we started at startU+0, the line would be crooked and too short.
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- for (int U = startU+1, V = startV; U <= endU; U += 1)
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+ // We already drew the start point. If we started at startU + 0, the line would be crooked and too short
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+ for (int u = startU + 1, v = startV; u <= endU; u++)
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{
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if (P >= 0)
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{
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- V += V_step; // Adjusts whenever we stray too far from the direct line. Details in the linked paper above.
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- P += B; // Remembers that we corrected our path.
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- }
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- else
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- {
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- P += A; // Remembers how far we are from the direct line.
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- }
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- if (is_x_y_reversed) // Substitutions may be in wrong order for drawing:
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- {
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- ImageDrawPixel(dst, U, V, color);
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- }
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- else
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- {
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- ImageDrawPixel(dst, V, U, color);
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+ v += stepV; // Adjusts whenever we stray too far from the direct line. Details in the linked paper above
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+ P += B; // Remembers that we corrected our path
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}
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+ else P += A; // Remembers how far we are from the direct line
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+
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+ if (reversedXY) ImageDrawPixel(dst, u, v, color);
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+ else ImageDrawPixel(dst, v, u, color);
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}
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}
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-
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+
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// Draw line within an image (Vector version)
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void ImageDrawLineV(Image *dst, Vector2 start, Vector2 end, Color color)
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{
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