[img]http://i.imgur.com/6O3ZEmX.gif[/img] The example project is for GM studio 1.2 https://www.dropbox.com/sh/vrqorbpbwdh4dcz/AAA4pl30-Ij3s0Q0oFRXpAvja?dl=0 However, the code only uses a few math functions like sqrt(), abs(),min(), max(), and dot_product() so it should be use-able for any GM version. However if you're only interested in the code, here's the script: [syntax=gml] var player = argument0; var triangle = argument1; /* This function does not take into account object flipX or flipY or scaling or non-topLeft sprite origins. You have to do that yourself. You would only have to edit the triangle points variables. The rest of the code remains the same. */ //bottom left point var tPx0 = triangle.x; var tPy0 = triangle.y + triangle.sprite_height; //top right point var tPx1 = triangle.x + triangle.sprite_width; var tPy1 = triangle.y + triangle.sprite_height + triangle.slopeY; //bottom right corner var tPx2 = tPx1; var tPy2 = tPy0; var tSlopeX = triangle.slopeX; var tSlopeY = triangle.slopeY; var tSlopeMagnitude = sqrt((tSlopeX *tSlopeX) + (tSlopeY * tSlopeY)); //get only the axis of the slope tSlopeX = tSlopeX / tSlopeMagnitude; tSlopeY = tSlopeY / tSlopeMagnitude; var output_intersecting = false; var output_minIntervalDistance = 100000; var output_translationAxisX = 0, output_translationAxisY = 0; var output_pushRectOutX = 0, output_pushRectOutY=0; var rLeft = player.x; var rTop = player.y; var rBottom = rTop + player.sprite_height; var rRight = rLeft + player.sprite_width; var minA, minB, maxA, maxB; var intervalDistance; var axisX, axisY; var centerOffsetX = .5 * (rLeft + rRight) - .5* (tPx0 + tPx1); var centerOffsetY = .5 * (rTop + rBottom) - .5* (tPy0 + tPy1); //Test for X axis //=========1. Find if the polygons are currently intersecting ====== axisX = 1; axisY = 0; //project the rectangle and triangle onto the X axis minA = rLeft; maxA = rRight; minB = dot_product(axisX,axisY, tPx0,tPy0); minB = min(minB, dot_product(axisX,axisY, tPx1,tPy1)); minB = min(minB, dot_product(axisX,axisY, tPx2,tPy2)); maxB = dot_product(axisX, axisY, tPx0, tPy0); maxB = max(maxB, dot_product(axisX, axisY, tPx1, tPy1)); maxB = max(maxB, dot_product(axisX, axisY, tPx2, tPy2)); ////Check if the polygon projections are currently intersecting //if the distance is positive, there is no overlap if (minA < minB) intervalDistance= minB - maxA; else intervalDistance= minA - maxB; if (intervalDistance> 0) { output_intersecting = false; return false; } //Check if the current interval distance is the minimum one. If so store //the interval distance and the current distance. //This will be used to calculate the minimum translation vector. intervalDistance = abs(intervalDistance); if (intervalDistance < output_minIntervalDistance) { output_minIntervalDistance = intervalDistance; output_translationAxisX = axisX; output_translationAxisY = axisY; //this causes the translation axis to be relative to how much to push A out of B if (dot_product(centerOffsetX, centerOffsetY, output_translationAxisX, output_translationAxisY) < 0) { output_translationAxisX = output_translationAxisX * -1; output_translationAxisY = output_translationAxisY * -1; } output_pushRectOutX = output_translationAxisX * output_minIntervalDistance; output_pushRectOutY = output_translationAxisY * output_minIntervalDistance; } //Test for Y axis //=========1. Find if the polygons are currently intersecting ====== axisX = 0; axisY = 1; //project the rectangle and triangle minA = rTop; maxA = rBottom; minB = dot_product(axisX,axisY, tPx0,tPy0); minB = min(minB, dot_product(axisX,axisY, tPx1,tPy1)); minB = min(minB, dot_product(axisX,axisY, tPx2,tPy2)); maxB = dot_product(axisX, axisY, tPx0, tPy0); maxB = max(maxB, dot_product(axisX, axisY, tPx1, tPy1)); maxB = max(maxB, dot_product(axisX, axisY, tPx2, tPy2)); ////Check if the polygon projections are currently intersecting //if the distance is positive so there is no overlap if (minA < minB) intervalDistance= minB - maxA; else intervalDistance= minA - maxB; if (intervalDistance> 0) { output_intersecting = false; return false; } //Check if the current interval distance is the minimum one. If so store //the interval distance and the current distance. //This will be used to calculate the minimum translation vector. intervalDistance = abs(intervalDistance); if (intervalDistance < output_minIntervalDistance) { output_minIntervalDistance = intervalDistance; output_translationAxisX = axisX; output_translationAxisY = axisY; //this causes the translation axis to be relative to how much to push A out of B if (dot_product(centerOffsetX, centerOffsetY, output_translationAxisX, output_translationAxisY) < 0) { output_translationAxisX = output_translationAxisX * -1; output_translationAxisY = output_translationAxisY * -1; } output_pushRectOutX = output_translationAxisX * output_minIntervalDistance; output_pushRectOutY = output_translationAxisY * output_minIntervalDistance; } //Test for Slope axis //=========1. Find if the polygons are currently intersecting ====== // we must use the perpendicular axis to the slope axisX = tSlopeY; axisY = -tSlopeX; //project the rectangle and triangle minA = dot_product(axisX,axisY, rLeft,rTop); minA = min(minA, dot_product(axisX,axisY, rRight,rTop)); minA = min(minA, dot_product(axisX,axisY, rRight,rBottom)); minA = min(minA, dot_product(axisX,axisY, rLeft,rBottom)); maxA = dot_product(axisX,axisY, rLeft,rTop); maxA = max(maxA, dot_product(axisX,axisY, rRight,rTop)); maxA = max(maxA, dot_product(axisX,axisY, rRight,rBottom)); maxA = max(maxA, dot_product(axisX,axisY, rLeft,rBottom)); minB = dot_product(axisX,axisY, tPx0,tPy0); minB = min(minB, dot_product(axisX,axisY, tPx1,tPy1)); minB = min(minB, dot_product(axisX,axisY, tPx2,tPy2)); maxB = dot_product(axisX, axisY, tPx0, tPy0); maxB = max(maxB, dot_product(axisX, axisY, tPx1, tPy1)); maxB = max(maxB, dot_product(axisX, axisY, tPx2, tPy2)); ////Check if the polygon projections are currently intersecting //if the distance is positive so there is no overlap if (minA < minB) intervalDistance= minB - maxA; else intervalDistance= minA - maxB; if (intervalDistance> 0) { output_intersecting = false; return false; } //Check if the current interval distance is the minimum one. If so store //the interval distance and the current distance. //This will be used to calculate the minimum translation vector. intervalDistance = abs(intervalDistance); if (intervalDistance < output_minIntervalDistance) { output_minIntervalDistance = intervalDistance; output_translationAxisX = axisX; output_translationAxisY = axisY; //this causes the translation axis to be relative to how much to push A out of B if (dot_product(centerOffsetX, centerOffsetY, output_translationAxisX, output_translationAxisY) < 0) { output_translationAxisX = output_translationAxisX * -1; output_translationAxisY = output_translationAxisY * -1; } output_pushRectOutX = output_translationAxisX * output_minIntervalDistance; output_pushRectOutY = output_translationAxisY * output_minIntervalDistance; } //if we've made it to this point, we know the rectangle and triangle are intersecting output_intersecting = true; player.x = player.x + output_pushRectOutX; player.y = player.y + output_pushRectOutY; return true; [/syntax] If you're interested in how it works, it's the separating axis theorem, but limited to support only rectangle to triangle overlaps. For the example project, argument0 refers to the player or rectangle and argument1 refers to the triangle or slope. Triangle objects must have the instance variables "slopeX" and "slopeY" which represents the width and height of the slope. For example, for the 32x32 slopes above, slopeX = 32, slopeY = -32. Both the player and slope have their topLeft as the origin. Here, I just call the script at the end of the step for each triangle object. The output____ variables give info for whether there is an overlap (output_intersecting), the direction that the rectangle is pushed out of (output_translationAxis), the amount it's pushed (output_minIntervalDistance), and the vector offset it's pushed (output_pushRectOut). Of course, you can change the script to your liking. It doesn't support flipped sprites, non-top-left sprite origins, or scaling. To support them, you just have to change the points for the triangle and bounds of the rectangle. If there are any bugs with the code above, let me know and I'll figure it out. [b]If you do add more support, please share the code for others too. Post it here.[/b]