draftx 符号调整为正数
发现采样坐标系原点0，0 在左上角，正方向 右，下
绘制坐标系 原点0，0 在左下角，正方向 右，上
拖拽可得
#include <raylib.h>
// 重整原因：解决新函数放大缩小之下，raylib 的网格采样部分，选择数组的一部分刷新倒缓冲区里
// 从直接建立缓冲区，到先在数组里进行移动，然后再设置检查缓冲区int main() {int **map;map = new int*[250];for (int i = 0; i < 250; i++) {map[i] = new int[250];}for (int i = 0; i < 250; i++) {for (int j = 0; j < 250; j++) {
// 测试数据，渐变 25改105 柔和map[i][j] = (j + i) % 105;}}// 初始化窗口InitWindow(1750, 1050, "test for location");
// 设置GPU可以操作的画布,一定要再初始化窗口之后才行，实际上是OpenGL的上下文，或者说默认环境设置RenderTexture2D mesh = LoadRenderTexture(750 + 30 * 2, 750 + 30 * 2);
// 设置帧率SetTargetFPS(160);
// 设置默认绘制到meshBeginTextureMode(mesh);for (int i = 0; i < 25; i++) {for (int j = 0; j < 25; j++) {
// 绘制矩形,原点(0,0)在左下角,现在是从左下角一行一行往上绘制if (i == 0 || j == 0 || i == 24 || j == 24) {DrawRectangle(j * 30, i * 30, 30, 30, {0, 255, 255, 255});} else {DrawRectangle(j * 30, i * 30, 30, 30, {map[i][j] * 5 % 255, map[i][j] * 5 % 255, 255, 255});}}}
// 取消绘制的GPU画布EndTextureMode();
// 设置默认绘制到桌面BeginDrawing();
// 黑色覆盖全部屏幕ClearBackground(BLACK);DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {0, 0, 750, 750}, {0, 0}, 0, WHITE);
// 结束绘制的桌面EndDrawing();int mousex;int mousey;mousex = 0;mousey = 0;float camerasize;camerasize = 1;
// 拖拽int draftflag;int draftx;int drafty;int gamex;int gamey;
// 记录长按时，鼠标按下去的位置，减出长按拖拽距离int oldx;int oldy;draftflag = 0;draftx = 0;drafty = 0;gamex = 0;gamey = 0;// 记录bkmeshmap 网格,用于出界刷新int bkmeshmapi;int bkmeshmapj;int bkmeshmapmaxi;int bkmeshmapmaxj;bkmeshmapi = 0;bkmeshmapi = 0;bkmeshmapmaxi = 25 + 2;bkmeshmapmaxj = 25 + 2;// 拖拽边界int limitright;int limitleft;int limittop;int limitbottom;// 坐标系变化，现在是在底部进行，左下角是0，0原点limitright = 25 * 30 + 30 * 2;limitleft = 0;limittop = 25 * 30 + 30 * 2;limitbottom = 0;// 这里开始主循环while (!WindowShouldClose()) {
// 注意是pressed 不是 Downif (IsMouseButtonPressed(MOUSE_BUTTON_RIGHT)) {draftflag = 1;oldx = GetMouseX();oldy = GetMouseY();}if (draftflag == 1) {mousex = GetMouseX();mousey = GetMouseY();draftx = gamex - (mousex - oldx) / camerasize;drafty = gamey - (mousey - oldy) / camerasize;}if (IsMouseButtonUp(MOUSE_BUTTON_RIGHT)) {draftflag = 0;oldx = 0;oldy = 0;gamex = draftx;gamey = drafty;}if (draftx < limitleft && draftx > 30) {bkmeshmapj - 1;limitleft -= 30;} else if (draftx > limitright + bkmeshmapi * 30 && draftx < 250 * 30 - 750 - 30) {bkmeshmapj + 1;limitright += 30;}if (drafty < limitbottom && drafty > 30) {bkmeshmapj - 1;limittop -= 30;} else if (draftx > limittop && drafty < 250 * 30 - 750 - 30) {bkmeshmapj + 1;limitbottom += 30;}// 设置默认绘制到meshBeginTextureMode(mesh);for (int i = 0; i < 25 + 2; i++) {for (int j = 0; j < 25 + 2; j++) {
// 绘制矩形,原点(0,0)在左下角,现在是从左下角一行一行往上绘制if (map[i][j] == 266) {DrawRectangle(j * 30, i * 30, 30, 30, {255, 0, 255, 255});} else {DrawRectangle(j * 30, i * 30, 30, 30, {map[i + bkmeshmapi][j + bkmeshmapj] * 5 % 255, map[i + bkmeshmapi][j + bkmeshmapj] * 5 % 255, 255, 255});}DrawRectangle(0, 0, 50, 50, {154, 154, 154, 255});
// 绘制坐标系是左下角0，0）y正方向向上}}
// 取消绘制的GPU画布EndTextureMode();
// 设置默认绘制到桌面BeginDrawing();
// 黑色覆盖全部屏幕ClearBackground(BLACK);
// 采样坐标系是左上角0，0，y轴正方向向下DrawTexturePro(mesh.texture, {draftx - bkmeshmapi * 30, drafty - bkmeshmapj * 30, 750 / camerasize, 750 / camerasize}, {0, 0, 750, 750}, {0, 0}, 0, WHITE);DrawText(TextFormat("mouseV1 %.0f,%.0f", GetMousePosition().x, GetMousePosition().y), 35, 12, 30, BLUE);DrawText(TextFormat("mouseV2 %.0f,%.0f", GetMousePosition().x, 750 - GetMousePosition().y), 35, 62, 30, BLUE);DrawText(TextFormat("draftxyV2 %d,%d", draftx, drafty), 35, 152, 30, RED);DrawText(TextFormat("camerasize %f", camerasize), 35, 192, 30, BLACK);
// 结束绘制的桌面EndDrawing();}
}
