SDL3/SDL_RenderGeometry

Render a list of triangles, optionally using a texture and indices into the vertex array Color and alpha modulation is done per vertex (SDL_SetTextureColorMod and SDL_SetTextureAlphaMod are ignored).

Header File

Syntax

bool SDL_RenderGeometry(SDL_Renderer *renderer,
                   SDL_Texture *texture,
                   const SDL_Vertex *vertices, int num_vertices,
                   const int *indices, int num_indices);

Function Parameters

Return Value

(bool) Returns true on success or false on failure; call SDL_GetError() for more information.

Thread Safety

Version

Code Examples

#include <SDL3/SDL.h>
#include <SDL3/SDL_main.h>

int main(int argc, char *argv[])
{
  bool quit = false;
  SDL_Window *window = SDL_CreateWindow("Triangle Example", 800, 600, 0);

  SDL_Renderer *renderer = SDL_CreateRenderer(window, NULL);

  #define vertLen 3
  SDL_Vertex vert[vertLen];

  // center
  vert[0].position.x = 400;
  vert[0].position.y = 150;
  vert[0].color.r = 1.0;
  vert[0].color.g = 0.0;
  vert[0].color.b = 0.0;
  vert[0].color.a = 1.0;

  // left
  vert[1].position.x = 200;
  vert[1].position.y = 450;
  vert[1].color.r = 0.0;
  vert[1].color.g = 0.0;
  vert[1].color.b = 1.0;
  vert[1].color.a = 1.0;

  // right
  vert[2].position.x = 600;
  vert[2].position.y = 450;
  vert[2].color.r = 0.0;
  vert[2].color.g = 1.0;
  vert[2].color.b = 0.0;
  vert[2].color.a = 1.0;

  while (!quit) {
   SDL_Event ev;
   while (SDL_PollEvent(&ev) != 0) {
      switch(ev.type) {
        case SDL_EVENT_QUIT:
        quit = true;
        break;
      }
    }
    SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
    SDL_RenderClear(renderer);

    SDL_RenderGeometry(renderer, NULL, vert, vertLen, NULL, 0);

    SDL_RenderPresent(renderer);
  }

  SDL_DestroyRenderer(renderer);
  SDL_DestroyWindow(window);
  SDL_Quit();
  return 0;
}

SDL_Renderer *	renderer	the rendering context.
SDL_Texture *	texture	(optional) The SDL texture to use.
const SDL_Vertex *	vertices	vertices.
int	num_vertices	number of vertices.
const int *	indices	(optional) An array of integer indices into the 'vertices' array, if NULL all vertices will be rendered in sequential order.
int	num_indices	number of indices.

(This is the documentation for SDL3, which is the current stable version. SDL2 was the previous version!)

SDL_RenderGeometry