this repo has no description
Updated circle angle coefficient and added a check to fix issues with small radius circles not having enough segments to complete the shape. Thanks GiovanniCmpaner for the report!
authored by
Jonathan Dearborn
and committed by
Alice
b9ea2a13
107c122c
+108
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+33
-15
src/renderer_shapes_GL_common.inl
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src/renderer_shapes_GL_common.inl
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#define SDL_GPU_CIRCLE_SEGMENT_ANGLE_FACTOR 0.625f
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#define CALCULATE_CIRCLE_DT_AND_SEGMENTS(radius) \
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dt = SDL_GPU_CIRCLE_SEGMENT_ANGLE_FACTOR/sqrtf(radius); /* s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good */ \
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numSegments = (int)(2*PI/dt) + 1; \
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\
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if(numSegments < 16) \
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{ \
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numSegments = 16; \
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dt = 2*PI/(numSegments-1); \
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}
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static float SetLineThickness(GPU_Renderer* renderer, float thickness)
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}
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dt = ((end_angle - start_angle)/360)*(1.25f/sqrtf(outer_radius)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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dt = ((end_angle - start_angle)/360)*(SDL_GPU_CIRCLE_SEGMENT_ANGLE_FACTOR/sqrtf(outer_radius)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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numSegments = (int)((fabs(end_angle - start_angle)*PI/180)/dt);
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if(numSegments == 0)
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end_angle -= 360;
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}
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dt = ((end_angle - start_angle)/360)*(1.25f/sqrtf(radius)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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dt = ((end_angle - start_angle)/360)*(SDL_GPU_CIRCLE_SEGMENT_ANGLE_FACTOR/sqrtf(radius)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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numSegments = (int)((fabs(end_angle - start_angle)*RAD_PER_DEG)/dt);
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if(numSegments == 0)
···
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float t = thickness/2;
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float inner_radius = radius - t;
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float outer_radius = radius + t;
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float dt = (1.25f/sqrtf(outer_radius)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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int numSegments = (int)(2*PI/dt)+1;
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float dt;
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int numSegments;
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CALCULATE_CIRCLE_DT_AND_SEGMENTS(outer_radius);
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float tempx;
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float c = cosf(dt);
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static void CircleFilled(GPU_Renderer* renderer, GPU_Target* target, float x, float y, float radius, SDL_Color color)
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{
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float dt = (1.25f/sqrtf(radius)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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float dt;
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float dx, dy;
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int numSegments = (int)(2*PI/dt)+1;
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int numSegments;
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int i;
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CALCULATE_CIRCLE_DT_AND_SEGMENTS(radius);
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float tempx;
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float c = cosf(dt);
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float outer_radius_x = rx + t;
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float inner_radius_y = ry - t;
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float outer_radius_y = ry + t;
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float dt = (1.25f/sqrtf(outer_radius_x > outer_radius_y? outer_radius_x : outer_radius_y)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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int numSegments = (int)(2*M_PI/dt)+1;
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float dt;
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int numSegments;
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CALCULATE_CIRCLE_DT_AND_SEGMENTS(outer_radius_x > outer_radius_y? outer_radius_x : outer_radius_y);
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float tempx;
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float c = cosf(dt);
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int i;
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float rot_x = cosf(degrees*RAD_PER_DEG);
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float rot_y = sinf(degrees*RAD_PER_DEG);
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float dt = (1.25f/sqrtf(rx > ry? rx : ry)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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int numSegments = (int)(2*M_PI/dt)+1;
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float dt;
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int numSegments;
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CALCULATE_CIRCLE_DT_AND_SEGMENTS(rx > ry? rx : ry);
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float tempx;
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float c = cosf(dt);
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t = start_angle;
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dt = ((end_angle - start_angle)/360)*(1.25f/sqrtf(outer_radius)) * DEG_PER_RAD; // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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dt = ((end_angle - start_angle)/360)*(SDL_GPU_CIRCLE_SEGMENT_ANGLE_FACTOR/sqrtf(outer_radius)) * DEG_PER_RAD; // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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numSegments = (int)(fabs(end_angle - start_angle)/dt);
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if(numSegments == 0)
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float t = thickness/2;
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float inner_radius = radius - t;
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float outer_radius = radius + t;
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float dt = (1.25f/sqrtf(outer_radius)); // s = rA, so dA = ds/r. ds of 1.25*sqrt(radius) is good, use A in degrees.
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int numSegments = (int)(2*PI/dt)+1;
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if(numSegments < 4)
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numSegments = 4;
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float dt;
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int numSegments;
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CALCULATE_CIRCLE_DT_AND_SEGMENTS(outer_radius);
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// Make a multiple of 4 so we can have even corners
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numSegments += numSegments % 4;
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tests/shapes/main.c
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tests/shapes/main.c
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#define M_PI 3.14159f
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#endif
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#define RANDOMIZE_SHAPE_DATA() \
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for(i = 0; i < NUM_COLORS; i++) \
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{ \
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colors[i].r = rand() % 256; \
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colors[i].g = rand() % 256; \
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colors[i].b = rand() % 256; \
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GET_ALPHA(colors[i]) = rand() % 256; \
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} \
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\
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for (i = 0; i < NUM_PIXELS; i++) \
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{ \
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px[i] = rand() % screen->w; \
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py[i] = rand() % screen->h; \
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} \
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\
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for (i = 0; i < NUM_LINES; i++) \
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{ \
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lx1[i] = rand() % screen->w; \
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ly1[i] = rand() % screen->h; \
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lx2[i] = rand() % screen->w; \
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ly2[i] = rand() % screen->h; \
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} \
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\
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for (i = 0; i < NUM_TRIS; i++) \
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{ \
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tx1[i] = rand() % screen->w; \
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ty1[i] = rand() % screen->h; \
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tx2[i] = rand() % screen->w; \
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ty2[i] = rand() % screen->h; \
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tx3[i] = rand() % screen->w; \
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ty3[i] = rand() % screen->h; \
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} \
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\
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for (i = 0; i < NUM_RECTS; i++) \
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{ \
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rx1[i] = rand() % screen->w; \
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ry1[i] = rand() % screen->h; \
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rx2[i] = rand() % screen->w; \
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ry2[i] = rand() % screen->h; \
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rr[i] = rand() % 10 + 2; \
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} \
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\
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for (i = 0; i < NUM_ARCS; i++) \
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{ \
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ax[i] = rand() % screen->w; \
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ay[i] = rand() % screen->h; \
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ar[i] = (rand() % screen->h) / 10.0f; \
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ar2[i] = ((rand() % 101) / 100.0f) * ar[i]; \
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aa1[i] = rand() % 360; \
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aa2[i] = rand() % 360; \
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} \
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\
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for (i = 0; i < NUM_POLYS; i++) \
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{ \
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float cx = rand() % screen->w; \
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float cy = rand() % screen->h; \
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float radius = 20 + rand() % (screen->w / 8); \
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\
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int j; \
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\
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pn[i] = rand() % 8 + 3; \
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pv[i] = (float*)malloc(2 * pn[i] * sizeof(float)); \
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\
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for (j = 0; j < pn[i] * 2; j += 2) \
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{ \
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pv[i][j] = cx + radius * cos(2 * M_PI * (((float)j) / (pn[i] * 2))) + rand() % ((int)radius / 2); \
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pv[i][j + 1] = cy + radius * sin(2 * M_PI * (((float)j) / (pn[i] * 2))) + rand() % ((int)radius / 2); \
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} \
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}
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int main(int argc, char* argv[])
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{
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GPU_Target* screen;
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shapeType = 0;
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numShapeTypes = 18;
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for(i = 0; i < NUM_COLORS; i++)
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{
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colors[i].r = rand()%256;
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colors[i].g = rand()%256;
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colors[i].b = rand()%256;
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GET_ALPHA(colors[i]) = rand()%256;
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}
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for(i = 0; i < NUM_PIXELS; i++)
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{
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px[i] = rand()%screen->w;
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py[i] = rand()%screen->h;
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}
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for(i = 0; i < NUM_LINES; i++)
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{
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lx1[i] = rand()%screen->w;
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ly1[i] = rand()%screen->h;
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lx2[i] = rand()%screen->w;
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ly2[i] = rand()%screen->h;
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}
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for(i = 0; i < NUM_TRIS; i++)
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{
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tx1[i] = rand()%screen->w;
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ty1[i] = rand()%screen->h;
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tx2[i] = rand()%screen->w;
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ty2[i] = rand()%screen->h;
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tx3[i] = rand()%screen->w;
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ty3[i] = rand()%screen->h;
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}
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for(i = 0; i < NUM_RECTS; i++)
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{
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rx1[i] = rand()%screen->w;
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ry1[i] = rand()%screen->h;
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rx2[i] = rand()%screen->w;
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ry2[i] = rand()%screen->h;
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rr[i] = rand()%10 + 2;
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}
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for(i = 0; i < NUM_ARCS; i++)
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{
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ax[i] = rand()%screen->w;
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ay[i] = rand()%screen->h;
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ar[i] = (rand()%screen->h)/10.0f;
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ar2[i] = ((rand()%101)/100.0f)*ar[i];
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aa1[i] = rand()%360;
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aa2[i] = rand()%360;
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}
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for(i = 0; i < NUM_POLYS; i++)
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{
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float cx = rand()%screen->w;
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float cy = rand()%screen->h;
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float radius = 20 + rand()%(screen->w/8);
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int j;
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pn[i] = rand()%8 + 3;
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pv[i] = (float*)malloc(2*pn[i]*sizeof(float));
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for(j = 0; j < pn[i]*2; j+=2)
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{
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pv[i][j] = cx + radius*cos(2*M_PI*(((float)j)/(pn[i]*2))) + rand()%((int)radius/2);
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pv[i][j+1] = cy + radius*sin(2*M_PI*(((float)j)/(pn[i]*2))) + rand()%((int)radius/2);
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}
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}
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RANDOMIZE_SHAPE_DATA();
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blend = 0;
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thickness = 1.0f;
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{
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blend = !blend;
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GPU_SetShapeBlending(blend);
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}
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else if(event.key.keysym.sym == SDLK_RETURN)
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{
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RANDOMIZE_SHAPE_DATA();
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}
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else if(event.key.keysym.sym == SDLK_UP || event.key.keysym.sym == SDLK_EQUALS)
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{