如果在shader_set()和shader_reset()之间调用draw_self()，那么精灵就不会绘制出来。

VSH代码：

attribute vec3 in_Position; 
varying vec2 fragCoord; 
void main() {
vec4 Position = vec4( in_Position, 1.0); 
gl_Position = gm_Matrices[MATRIX_WORLD_VIEW_PROJECTION] * Position; 
fragCoord = in_Position.xy; 
}

FSH代码：

uniform float iGlobalTime; 
uniform vec3 iResolution; 
varying vec2 fragCoord; 

void main(){
#define PSX_MODE

#ifdef PSX_MODE
#define INT_VERTICES
vec2 RESOLUTION = vec2(320.0, 240.0);
const float FPS = 25.0;
#else
#define BILINEAR
#define RESOLUTION iResolution.xy
const float FPS = 60.0;
#endif
}

// math
float _cross(vec2 a, vec2 b) {
return a.x * b.y - a.y * b.x;
}