An image rendering method that is executed by a processing device, the method comprising: acquiring a water wave map corresponding to a target water body region where a dynamic object is located in a current image frame, wherein a water surface of the target water body region is divided into blocks and the water wave map is formed by information of water surface height displacements of vertexes of the blocks of the water surface; acquiring a normal map corresponding to the target water body region where the dynamic object is located in a next image frame based on the water wave map corresponding to the target water body region where the dynamic object is located in the current image frame; and rendering a water wave effect on the target water body region where the dynamic object is located in the next image frame based on the normal map corresponding to the target water body region where the dynamic object is located in the next image frame, characterized in that the method further comprises: providing a first render texture to store the water wave map of the current image frame, a second render texture to store a water wave map of the next image frame and a third render texture to store the normal map of the next image frame, the first, second and third render textures use a rendering map format with only two color channels; storing water surface height displacements of a previous image frame and the current image frame in the two color channels of the first render texture, respectively; storing the water surface height displacements of the current image frame and the next image frame in the two color channels of the second render texture, respectively; and storing water surface height displacement differences between each vertex and two vertexes neighboring to the vertex in the next image frame in the two color channels of the third render texture, respectively. acquiring a water wave map corresponding to a target water body region where a dynamic object is located in a current image frame, wherein a water surface of the target water body region is divided into blocks and the water wave map is formed by information of water surface height displacements of vertexes of the blocks of the water surface; acquiring a normal map corresponding to the target water body region where the dynamic object is located in a next image frame based on the water wave map corresponding to the target water body region where the dynamic object is located in the current image frame; and rendering a water wave effect on the target water body region where the dynamic object is located in the next image frame based on the normal map corresponding to the target water body region where the dynamic object is located in the next image frame, characterized in that the method further comprises: providing a first render texture to store the water wave map of the current image frame, a second render texture to store a water wave map of the next image frame and a third render texture to store the normal map of the next image frame, the first, second and third render textures use a rendering map format with only two color channels; storing water surface height displacements of a previous image frame and the current image frame in the two color channels of the first render texture, respectively; storing the water surface height displacements of the current image frame and the next image frame in the two color channels of the second render texture, respectively; and storing water surface height displacement differences between each vertex and two vertexes neighboring to the vertex in the next image frame in the two color channels of the third render texture, respectively. providing a first render texture to store the water wave map of the current image frame, a second render texture to store a water wave map of the next image frame and a third render texture to store the normal map of the next image frame, the first, second and third render textures use a rendering map format with only two color channels; storing water surface height displacements of a previous image frame and the current image frame in the two color channels of the first render texture, respectively; storing the water surface height displacements of the current image frame and the next image frame in the two color channels of the second render texture, respectively; and storing water surface height displacement differences between each vertex and two vertexes neighboring to the vertex in the next image frame in the two color channels of the third render texture, respectively.