Add RenderPolyLinesEx routine (#1758)

Co-authored-by: Lambert Wang <lambert.ww@gmail.com>

examples/shapes/shapes_basic_shapes.c

@@ -39,27 +39,32 @@ int main(void)
 
             DrawText("some basic shapes available on raylib", 20, 20, 20, DARKGRAY);
 
-            DrawCircle(screenWidth/4, 120, 35, DARKBLUE);
+            // Circle shapes and lines
+            DrawCircle(screenWidth/5, 120, 35, DARKBLUE);
+            DrawCircleGradient(screenWidth/5, 220, 60, GREEN, SKYBLUE);
+            DrawCircleLines(screenWidth/5, 340, 80, DARKBLUE);
 
+            // Rectangle shapes and ines
             DrawRectangle(screenWidth/4*2 - 60, 100, 120, 60, RED);
-            DrawRectangleLines(screenWidth/4*2 - 40, 320, 80, 60, ORANGE);  // NOTE: Uses QUADS internally, not lines
             DrawRectangleGradientH(screenWidth/4*2 - 90, 170, 180, 130, MAROON, GOLD);
+            DrawRectangleLines(screenWidth/4*2 - 40, 320, 80, 60, ORANGE);  // NOTE: Uses QUADS internally, not lines
 
+            // Triangle shapes and lines
             DrawTriangle((Vector2){screenWidth/4.0f *3.0f, 80.0f},
                          (Vector2){screenWidth/4.0f *3.0f - 60.0f, 150.0f},
                          (Vector2){screenWidth/4.0f *3.0f + 60.0f, 150.0f}, VIOLET);
 
-            DrawPoly((Vector2){screenWidth/4*3, 320}, 6, 80, 0, BROWN);
+            DrawTriangleLines((Vector2){screenWidth/4.0f*3.0f, 160.0f},
+                              (Vector2){screenWidth/4.0f*3.0f - 20.0f, 230.0f},
+                              (Vector2){screenWidth/4.0f*3.0f + 20.0f, 230.0f}, DARKBLUE);
 
-            DrawCircleGradient(screenWidth/4, 220, 60, GREEN, SKYBLUE);
+            // Polygon shapes and lines
+            DrawPoly((Vector2){screenWidth/4*3, 320}, 6, 80, 0, BROWN);
+            DrawPolyLinesEx((Vector2){screenWidth/4*3, 320}, 6, 80, 0, 6, BEIGE);
 
             // NOTE: We draw all LINES based shapes together to optimize internal drawing,
             // this way, all LINES are rendered in a single draw pass
             DrawLine(18, 42, screenWidth - 18, 42, BLACK);
-            DrawCircleLines(screenWidth/4, 340, 80, DARKBLUE);
-            DrawTriangleLines((Vector2){screenWidth/4.0f*3.0f, 160.0f},
-                              (Vector2){screenWidth/4.0f*3.0f - 20.0f, 230.0f},
-                              (Vector2){screenWidth/4.0f*3.0f + 20.0f, 230.0f}, DARKBLUE);
         EndDrawing();
         //----------------------------------------------------------------------------------
     }

src/raylib.h

@@ -1172,15 +1172,16 @@ RLAPI void DrawRectangleGradientV(int posX, int posY, int width, int height, Col
 RLAPI void DrawRectangleGradientH(int posX, int posY, int width, int height, Color color1, Color color2);// Draw a horizontal-gradient-filled rectangle
 RLAPI void DrawRectangleGradientEx(Rectangle rec, Color col1, Color col2, Color col3, Color col4);       // Draw a gradient-filled rectangle with custom vertex colors
 RLAPI void DrawRectangleLines(int posX, int posY, int width, int height, Color color);                   // Draw rectangle outline
-RLAPI void DrawRectangleLinesEx(Rectangle rec, int lineThick, Color color);                              // Draw rectangle outline with extended parameters
+RLAPI void DrawRectangleLinesEx(Rectangle rec, float lineThick, Color color);                            // Draw rectangle outline with extended parameters
 RLAPI void DrawRectangleRounded(Rectangle rec, float roundness, int segments, Color color);              // Draw rectangle with rounded edges
-RLAPI void DrawRectangleRoundedLines(Rectangle rec, float roundness, int segments, int lineThick, Color color); // Draw rectangle with rounded edges outline
+RLAPI void DrawRectangleRoundedLines(Rectangle rec, float roundness, int segments, float lineThick, Color color); // Draw rectangle with rounded edges outline
 RLAPI void DrawTriangle(Vector2 v1, Vector2 v2, Vector2 v3, Color color);                                // Draw a color-filled triangle (vertex in counter-clockwise order!)
 RLAPI void DrawTriangleLines(Vector2 v1, Vector2 v2, Vector2 v3, Color color);                           // Draw triangle outline (vertex in counter-clockwise order!)
 RLAPI void DrawTriangleFan(Vector2 *points, int pointsCount, Color color);                               // Draw a triangle fan defined by points (first vertex is the center)
 RLAPI void DrawTriangleStrip(Vector2 *points, int pointsCount, Color color);                             // Draw a triangle strip defined by points
 RLAPI void DrawPoly(Vector2 center, int sides, float radius, float rotation, Color color);               // Draw a regular polygon (Vector version)
 RLAPI void DrawPolyLines(Vector2 center, int sides, float radius, float rotation, Color color);          // Draw a polygon outline of n sides
+RLAPI void DrawPolyLinesEx(Vector2 center, int sides, float radius, float rotation, float lineThick, Color color); // Draw a polygon outline of n sides with extended parameters
 
 // Basic shapes collision detection functions
 RLAPI bool CheckCollisionRecs(Rectangle rec1, Rectangle rec2);                                           // Check collision between two rectangles

src/shapes.c

@@ -766,7 +766,7 @@ void DrawRectangleLines(int posX, int posY, int width, int height, Color color)
 }
 
 // Draw rectangle outline with extended parameters
-void DrawRectangleLinesEx(Rectangle rec, int lineThick, Color color)
+void DrawRectangleLinesEx(Rectangle rec, float lineThick, Color color)
 {
     if ((lineThick > rec.width) || (lineThick > rec.height))
     {
@@ -784,11 +784,11 @@ void DrawRectangleLinesEx(Rectangle rec, int lineThick, Color color)
     //   BBBBBBBB
     //   BBBBBBBB
     //
-    float thick = (float)lineThick;
+
-    Rectangle top = { rec.x, rec.y, rec.width, thick };
+    Rectangle top = { rec.x, rec.y, rec.width, lineThick };
-    Rectangle bottom = { rec.x, rec.y - thick + rec.height, rec.width, thick };
+    Rectangle bottom = { rec.x, rec.y - lineThick + rec.height, rec.width, lineThick };
-    Rectangle left = { rec.x, rec.y + thick, thick, rec.height - thick*2.0f };
+    Rectangle left = { rec.x, rec.y + lineThick, lineThick, rec.height - lineThick*2.0f };
-    Rectangle right = { rec.x - thick + rec.width, rec.y + thick, thick, rec.height - thick*2.0f };
+    Rectangle right = { rec.x - lineThick + rec.width, rec.y + lineThick, lineThick, rec.height - lineThick*2.0f };
 
     DrawRectangleRec(top, color);
     DrawRectangleRec(bottom, color);
@@ -1019,7 +1019,7 @@ void DrawRectangleRounded(Rectangle rec, float roundness, int segments, Color co
 }
 
 // Draw rectangle with rounded edges outline
-void DrawRectangleRoundedLines(Rectangle rec, float roundness, int segments, int lineThick, Color color)
+void DrawRectangleRoundedLines(Rectangle rec, float roundness, int segments, float lineThick, Color color)
 {
     if (lineThick < 0) lineThick = 0;
 
@@ -1046,7 +1046,7 @@ void DrawRectangleRoundedLines(Rectangle rec, float roundness, int segments, int
     }
 
     float stepLength = 90.0f/(float)segments;
-    const float outerRadius = radius + (float)lineThick, innerRadius = radius;
+    const float outerRadius = radius + lineThick, innerRadius = radius;
 
     /*
     Quick sketch to make sense of all of this,
@@ -1379,7 +1379,11 @@ void DrawPoly(Vector2 center, int sides, float radius, float rotation, Color col
     if (sides < 3) sides = 3;
     float centralAngle = 0.0f;
 
-    rlCheckRenderBatchLimit(4*(360/sides));
+#if defined(SUPPORT_QUADS_DRAW_MODE)
+    rlCheckRenderBatchLimit(4*sides); // Each side is a quad
+#else
+    rlCheckRenderBatchLimit(3*sides);
+#endif
 
     rlPushMatrix();
         rlTranslatef(center.x, center.y, 0.0f);
@@ -1431,7 +1435,7 @@ void DrawPolyLines(Vector2 center, int sides, float radius, float rotation, Colo
     if (sides < 3) sides = 3;
     float centralAngle = 0.0f;
 
-    rlCheckRenderBatchLimit(3*(360/sides));
+    rlCheckRenderBatchLimit(2*sides);
 
     rlPushMatrix();
         rlTranslatef(center.x, center.y, 0.0f);
@@ -1450,6 +1454,68 @@ void DrawPolyLines(Vector2 center, int sides, float radius, float rotation, Colo
     rlPopMatrix();
 }
 
+void DrawPolyLinesEx(Vector2 center, int sides, float radius, float rotation, float lineThick, Color color)
+{
+    if (sides < 3) sides = 3;
+    float centralAngle = 0.0f;
+    float exteriorAngle = 360.0f/(float)sides;
+    float innerRadius = radius - (lineThick*cosf(DEG2RAD*exteriorAngle/2.0f));
+
+#if defined(SUPPORT_QUADS_DRAW_MODE)
+    rlCheckRenderBatchLimit(4*sides);
+#else
+    rlCheckRenderBatchLimit(6*sides);
+#endif
+
+    rlPushMatrix();
+        rlTranslatef(center.x, center.y, 0.0f);
+        rlRotatef(rotation, 0.0f, 0.0f, 1.0f);
+
+#if defined(SUPPORT_QUADS_DRAW_MODE)
+        rlSetTexture(texShapes.id);
+
+        rlBegin(RL_QUADS);
+            for (int i = 0; i < sides; i++)
+            {
+                rlColor4ub(color.r, color.g, color.b, color.a);
+
+                rlTexCoord2f(texShapesRec.x/texShapes.width, texShapesRec.y/texShapes.height);
+                rlVertex2f(sinf(DEG2RAD*centralAngle)*innerRadius, cosf(DEG2RAD*centralAngle)*innerRadius);
+
+                rlTexCoord2f(texShapesRec.x/texShapes.width, (texShapesRec.y + texShapesRec.height)/texShapes.height);
+                rlVertex2f(sinf(DEG2RAD*centralAngle)*radius, cosf(DEG2RAD*centralAngle)*radius);
+
+                centralAngle += exteriorAngle;
+                rlTexCoord2f((texShapesRec.x + texShapesRec.width)/texShapes.width, texShapesRec.y/texShapes.height);
+                rlVertex2f(sinf(DEG2RAD*centralAngle)*radius, cosf(DEG2RAD*centralAngle)*radius);
+
+                rlTexCoord2f((texShapesRec.x + texShapesRec.width)/texShapes.width, (texShapesRec.y + texShapesRec.height)/texShapes.height);
+                rlVertex2f(sinf(DEG2RAD*centralAngle)*innerRadius, cosf(DEG2RAD*centralAngle)*innerRadius);
+            }
+        rlEnd();
+        rlSetTexture(0);
+#else
+        rlBegin(RL_TRIANGLES);
+            for (int i = 0; i < sides; i++)
+            {
+                rlColor4ub(color.r, color.g, color.b, color.a);
+                float nextAngle = centralAngle + exteriorAngle;
+
+                rlVertex2f(sinf(DEG2RAD*centralAngle)*radius, cosf(DEG2RAD*centralAngle)*radius);
+                rlVertex2f(sinf(DEG2RAD*centralAngle)*innerRadius, cosf(DEG2RAD*centralAngle)*innerRadius);
+                rlVertex2f(sinf(DEG2RAD*nextAngle)*radius, cosf(DEG2RAD*nextAngle)*radius);
+
+                rlVertex2f(sinf(DEG2RAD*centralAngle)*innerRadius, cosf(DEG2RAD*centralAngle)*innerRadius);
+                rlVertex2f(sinf(DEG2RAD*nextAngle)*radius, cosf(DEG2RAD*nextAngle)*radius);
+                rlVertex2f(sinf(DEG2RAD*nextAngle)*innerRadius, cosf(DEG2RAD*nextAngle)*innerRadius);
+
+                centralAngle = nextAngle;
+            }
+        rlEnd();
+#endif
+    rlPopMatrix();
+}
+
 //----------------------------------------------------------------------------------
 // Module Functions Definition - Collision Detection functions
 //----------------------------------------------------------------------------------