通过750 - 鼠标坐标,把原点在左上角的鼠标坐标变成左下角
实现输入数据后的坐标系同GPU原点在左下角坐标相同,
比数组0,0对应左上角好,
此时实际上数组0,0对应左下角
#include <raylib.h>
// 感受:虽然是根据已有的经验进行移植,
//但是追随当时无中生有的过程,去理解当时如何基于最直接的穷举想出来的,
//沿着同样的测试穷举而不是照抄,因为有了另一个坐标系GPU左下角和鼠标左上角原点不同
//根据5.测试正方向 的注释:数格子发现一行一行对应之后,再修改鼠标坐标系,产生新的坐标学习
int main() {int **map;map = new int*[750 / 30];for (int i = 0; i < 25; i++) {map[i] = new int[25];}for (int i = 0; i < 25; i++) {for (int j = 0; j < 25; j++) {map[i][j] = 0;}}// 初始化窗口InitWindow(750, 750, "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, 750);
// 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 (map[i][j] == 0) {DrawRectangle(j * 30, i * 30, 30, 30, {255, 255, 255, 255});}if (i == 0 || j == 0 || i == 24 || j == 24) {DrawRectangle(j * 30, i * 30, 30, 30, {0, 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();
// 这里开始主循环int drawx;int drawy;int mousex;int mousey;int drawi;int drawj;mousex = 0;mousey = 0;drawx = 0;drawy = 0;drawi = 0;drawj = 0;while (!WindowShouldClose()) {
// 如果鼠标左键按下if (IsMouseButtonDown(MOUSE_BUTTON_LEFT)) {
// drawx = GetMousePosition().x;
// 无中生有坐标系变化过程
// 750,实际穷举描述得到,在点一下,在鼠标坐标系是0,100,靠顶边,
// 在GPU坐标系里0,100则是靠底边100像素,
// 然后实际上是直接取反然后加上高度上限,发现原来可以
// 最后重整旧测试代码实现
// drawy = 750 - GetMousePosition().y;
// drawy = 751 - GetMousePosition().y;
// if (drawx < 0 || drawx > 750 || drawy < 0 || drawy > 750)
// 发现可以直接写,标注数据变化,于是重新命名变量mousex = GetMousePosition().x;mousey = GetMousePosition().y;
// 测试之后,追加等号,发现等号设置在0处解决问题,750-0=750,750/30=25,数组出界,750-1=749,749/30=24,
// 可知减的多,不出界,剩下的少,于是就不出界if (mousex < 0 || mousex > 750 || mousey <= 0 || mousey > 750) {
// 如果出界就不绘制,因为长按时鼠标超出窗口仍然可以检测} else {
// 进行坐标系变换,禁用了原理代码drawx = mousex;drawy = 750 - mousey;drawj = drawx / 30;drawi = drawy / 30;map[drawi][drawj] = 1;}}// 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 (map[i][j] == 0) {DrawRectangle(j * 30, i * 30, 30, 30, {255, 255, 255, 255});} else if (map[i][j] == 1) {DrawRectangle(j * 30, i * 30, 30, 30, {255, 0, 0, 255});}
// 测试边界绘制时,禁用,看闪退有无时测试
// if (i == 0 || j == 0 || i == 24 || j == 24) {
// DrawRectangle(j * 30, i * 30, 30, 30, {0, 255, 255, 255});
// }if (i == 0 || j == 0 || i == 24 || j == 24) {DrawRectangle(j * 30, i * 30, 30, 30, {0, 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);
// 右移动100像素
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {100, 0, 750, 750}, {0, 0}, 0, WHITE);
// 左移动100像素
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {0, 0, 750, 750}, {100, 0}, 0, WHITE);
// 缩小到75*75大小像素
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {0, 0, 75, 75}, {0, 0}, 0, WHITE);
// 平移缩小的矩形右100像素
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {100, 0, 75, 75}, {0, 0}, 0, WHITE);
// 抵消
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {100, 0, 75, 75}, {100, 0}, 0, WHITE);
// 下移100像素
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {0, 100, 75, 75}, {0, 0}, 0, WHITE);
// 抵消了下移,回到原地,可知是上移
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {0, 100, 75, 75}, {0, 100}, 0, WHITE);
// 实锤上移像素
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {0, 0, 75, 75}, {0, 50}, 0, WHITE);
// 得出结论:后面的括号是管往左移动,往上移动,前面括号的两个数字往右,往下移动调节
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {0, 0, 75, 75}, {0, 50}, 0, WHITE);
// 但是可以负数反向,实现在一个括号里实现移动效果,可知是对应不同坐标系下,提供的快速适应方案
// DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {0, 0, 75, 75}, {0, -50}, 0, WHITE);
// 恢复原样DrawTexturePro(mesh.texture, {0, 0, 750, 750}, {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("drawjiV2 %d,%d", drawj, drawi), 35, 92, 30, BLUE);DrawText(TextFormat("drawxyV2 %d,%d", drawx, drawy), 35, 122, 30, BLUE);
// 结束绘制的桌面EndDrawing();}
}