From 89ec47f9619fa187cec575307cdc11ad836c40c5 Mon Sep 17 00:00:00 2001
From: Ivan Mahonin <bh@icystar.com>
Date: Sep 07 2020 07:37:42 +0000
Subject: fix stroke and framebuffer


---

diff --git a/src/drawing.c b/src/drawing.c
index c3198c0..feb3a10 100644
--- a/src/drawing.c
+++ b/src/drawing.c
@@ -152,13 +152,18 @@ void noClip()
 
 
 void projectionByViewport() {
+	unsigned int framebuffer_id = 0;
+	glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, (int*)&framebuffer_id);
 	int vp[4] = {};
 	glGetIntegerv(GL_VIEWPORT, vp);
 	unsigned int mode;
 	glGetIntegerv(GL_MATRIX_MODE, (int*)&mode);
 	glMatrixMode(GL_PROJECTION);
 	glLoadIdentity();
-	glOrtho(0, vp[2], vp[3], 0, -1.0, 1.0);
+	if (framebuffer_id)
+		glOrtho(0, vp[2], 0, vp[3], -1.0, 1.0);
+	else
+		glOrtho(0, vp[2], vp[3], 0, -1.0, 1.0);
 	glMatrixMode(mode);
 }
 
@@ -564,6 +569,8 @@ static void strokeAddCorner(
 	double kl0 = 1/l0, kl1 = 1/l1;
 	double nx0 = dx0*kl0, ny0 = dy0*kl0;
 	double nx1 = dx1*kl1, ny1 = dy1*kl1;
+	assert(fabs(sqrt(nx0*nx0 + ny0*ny0) - 1) <= HELI_PRECISION);
+	assert(fabs(sqrt(nx1*nx1 + ny1*ny1) - 1) <= HELI_PRECISION);
 	
 	double dot = nx0*ny1 - ny0*nx1;
 	if (dot > HELI_PRECISION) {
@@ -571,7 +578,7 @@ static void strokeAddCorner(
 		strokeAddPoint(stroke, x0, y0, ny0, -nx0);
 		strokeAddCornerSub(stroke, ny1, -nx1, precisionSqr, 8);
 	} else
-	if (dot < HELI_PRECISION) {
+	if (dot < -HELI_PRECISION) {
 		// corner
 		double dx = nx1 - nx0;
 		double dy = ny1 - ny0;
@@ -579,7 +586,7 @@ static void strokeAddCorner(
 		double nx = dx*kl, ny = dy*kl;
 		double c = nx*nx1 + ny*ny1;
 		double cl = 1/sqrt(1 - c*c);
-		if (cl > 3) cl = 3;
+		if (cl >  3) cl =  3;
 		strokeAddPoint(stroke, x0, y0, nx*cl, ny*cl);
 	} else {
 		// flat
@@ -729,6 +736,8 @@ static void pushPathPoint(double x, double y) {
 }
 
 static void endPath(int close, int stroke, int fill, int fillSimple) {
+	int origPathSize = pathSize;
+	
 	// remove duplicates
 	int removed = 0;
 	for(int i = 2; i < pathSize; i += 2) {
@@ -752,13 +761,22 @@ static void endPath(int close, int stroke, int fill, int fillSimple) {
 		pathSize -= 2;
 	
 	// draw
+	int isPoint = FALSE;
+	double px, py;
 	if (pathSize >= 4) {
 		if (fillSimple) drawFillSimple();
 			else if (fill) drawFill();
 		if (stroke) drawStroke(close);
+	} else
+	if (origPathSize >= 4 && stroke) {
+		px = path[0];
+		py = path[1];
+		isPoint = TRUE;
 	}
 	
 	resetPath();
+	
+	if (isPoint) point(px, py);
 }
 
 void closePath()
@@ -859,7 +877,7 @@ void heliDrawingPrepareFrame() {
 	
 	glEnable(GL_BLEND);
 	if (heliGLBlendFuncSeparatePtr)
-		heliGLBlendFuncSeparatePtr(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE);
+		heliGLBlendFuncSeparatePtr(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE_MINUS_DST_ALPHA, GL_ONE);
 	else
 		glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 	glEnable(GL_LINE_SMOOTH);
diff --git a/src/framebuffer.c b/src/framebuffer.c
index 06ead48..ea0e518 100644
--- a/src/framebuffer.c
+++ b/src/framebuffer.c
@@ -243,6 +243,9 @@ int imageFromViewport(int *outWidth, int *outHeight, unsigned char **outPixels) 
 	
 	if (vp[2] <= 0 || vp[3] <= 0) return FALSE;
 	
+	unsigned int prevR = 0, prevD = 0;
+	glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, (int*)&prevR);
+	
 	unsigned char *buffer = malloc(vp[2]*vp[3]*4);
 	glGetError();
 	glReadPixels(vp[0], vp[1], vp[2], vp[3], GL_RGBA, GL_UNSIGNED_BYTE, buffer);
@@ -257,8 +260,6 @@ int imageFromViewport(int *outWidth, int *outHeight, unsigned char **outPixels) 
 		HeliFramebufferDesc fbd = {};
 		heliInitFramebuffer(&fbd, vp[2], vp[3], NULL, FALSE, FALSE, FALSE, 0, TRUE);
 		
-		unsigned int prevR = 0, prevD = 0;
-		glGetIntegerv(GL_READ_FRAMEBUFFER_BINDING, (int*)&prevR);
 		glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, (int*)&prevD);
 		heliGLBindFramebufferPtr(GL_DRAW_FRAMEBUFFER, fbd.framebuffer_id);
 		heliGLBlitFramebufferPtr(vp[0], vp[1], vp[2], vp[3], 0, 0, vp[2], vp[3], GL_COLOR_BUFFER_BIT, GL_NEAREST);
@@ -271,14 +272,16 @@ int imageFromViewport(int *outWidth, int *outHeight, unsigned char **outPixels) 
 	}
 	
 	// flip image
-	size_t rowSize = vp[2]*4;
-	unsigned char *row = malloc(rowSize);
-	for(int i = vp[3]/2 - 1; i >= 0; --i) {
-		unsigned char *r0 = buffer + rowSize*i;
-		unsigned char *r1 = buffer + rowSize*(vp[3]-i-1);
-		memcpy(row, r0, rowSize);
-		memcpy(r0, r1, rowSize);
-		memcpy(r1, row, rowSize);
+	if (!prevR) {
+		size_t rowSize = vp[2]*4;
+		unsigned char *row = malloc(rowSize);
+		for(int i = vp[3]/2 - 1; i >= 0; --i) {
+			unsigned char *r0 = buffer + rowSize*i;
+			unsigned char *r1 = buffer + rowSize*(vp[3]-i-1);
+			memcpy(row, r0, rowSize);
+			memcpy(r0, r1, rowSize);
+			memcpy(r1, row, rowSize);
+		}
 	}
 	
 	*outWidth = vp[2];	
diff --git a/src/gl.c b/src/gl.c
index cdfbbba..98c95f2 100644
--- a/src/gl.c
+++ b/src/gl.c
@@ -186,7 +186,7 @@ void heliGLGetCommonState(HeliGLCommonState *state, unsigned int flags) {
 
 void heliGLSetCommonState(const HeliGLCommonState *state) {
 	int loadClip = state->flags & STATE_CLIP;
-	int loadTransform = state->flags & STATE_CLIP;
+	int loadTransform = state->flags & STATE_TRANSFORM;
 	if (loadClip) {
 		unsigned int mode;
 		glGetIntegerv(GL_MATRIX_MODE, (int*)&mode);